Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On 15 May 2015, at 10:03, andy pugh wrote: On 15 May 2015 at 02:02, Tom Easterday tom-...@bgp.nu wrote: I don’t have extra wire to do them individually and my wire is a multi-conductor (3 + ground). So I am going to put 4 ferrites together over the whole cable (including ground) You can just take the same 4-core wire 3x through the same ferrite. Ferrite chokes are interesting things, but its not a case of more turns is better, or any-ferrite-will-do. I was at a talk about making ferrite chokes on Wednesday evening, and You might find some techniques of interest at the speaker's site, here: http://www.ifwtech.co.uk/g3sek/ Look for the In Practice section towards the bottom of the page. The results from a properly tuned ferrite choke are impressive. Marcus -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On 15 May 2015 at 02:02, Tom Easterday tom-...@bgp.nu wrote: I don’t have extra wire to do them individually and my wire is a multi-conductor (3 + ground). So I am going to put 4 ferrites together over the whole cable (including ground) You can just take the same 4-core wire 3x through the same ferrite. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On Friday 15 May 2015 05:43:14 Marcus Bowman wrote: On 15 May 2015, at 10:03, andy pugh wrote: On 15 May 2015 at 02:02, Tom Easterday tom-...@bgp.nu wrote: I don’t have extra wire to do them individually and my wire is a multi-conductor (3 + ground). So I am going to put 4 ferrites together over the whole cable (including ground) You can just take the same 4-core wire 3x through the same ferrite. Ferrite chokes are interesting things, but its not a case of more turns is better, or any-ferrite-will-do. I was at a talk about making ferrite chokes on Wednesday evening, and You might find some techniques of interest at the speaker's site, here: http://www.ifwtech.co.uk/g3sek/ Look for the In Practice section towards the bottom of the page. The results from a properly tuned ferrite choke are impressive. So are the results of taking a ferrite above its curie temperature while under power. And many of those very impressive ferrites have a curie temp well below boiling water... Marcus -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene Heskett -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) Genes Web page http://geneslinuxbox.net:6309/gene -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I spent some time with the spectrum analyzer but did’t have much luck in isolating the sink for the noise. I just verified that my VFD does indeed produce a large amount of noise between low kHz and about 10MHz! I did some re-routing of wires and replaced some that weren’t shielded. I ordered some ferrites for the VFD-motor wiring and my computer I/O extension cabling which will be here in a couple days. However, I did find the source of the main problem! It was indeed my keyboard. Not the USB wiring from keyboard to pc, but the keyboard ITSELF is very sensitive to the noise created by the VFD. If I move the keyboard to the very extreme end of it’s (rather long) usb cable the problem disappears completely. 6” closer to the cabinet and noise reappears. Apparently the noise is being interpreted as key presses by the keyboard circuitry. I replaced the new water resistant Logitech keyboard with a very old Apple keyboard I had lying around and no more random characters! I also had a second problem where the VFD would shut down somewhat randomly which I thought was related to this noise as well. That turned out to be an over current condition at very low rpm. Tweaking some settings fixed that. The Rasmi input filter, and various re-wiring and shielding I did was probably not needed, but in the long run perhaps it will save me from other problems. Thanks, for all the input, -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
The Rasmi input filter Take it off and see what happens If that drive is screwing with your keyboard that is on the OUTSIDE of your control cabinet, imagine what kind of RF exposure is on the inside of your control cabinet! Those AD VFDs should also be sold as EMI test generators. ;-) Dave On 5/14/2015 8:53 AM, Tom Easterday wrote: I spent some time with the spectrum analyzer but did’t have much luck in isolating the sink for the noise. I just verified that my VFD does indeed produce a large amount of noise between low kHz and about 10MHz! I did some re-routing of wires and replaced some that weren’t shielded. I ordered some ferrites for the VFD-motor wiring and my computer I/O extension cabling which will be here in a couple days. However, I did find the source of the main problem! It was indeed my keyboard. Not the USB wiring from keyboard to pc, but the keyboard ITSELF is very sensitive to the noise created by the VFD. If I move the keyboard to the very extreme end of it’s (rather long) usb cable the problem disappears completely. 6” closer to the cabinet and noise reappears. Apparently the noise is being interpreted as key presses by the keyboard circuitry. I replaced the new water resistant Logitech keyboard with a very old Apple keyboard I had lying around and no more random characters! I also had a second problem where the VFD would shut down somewhat randomly which I thought was related to this noise as well. That turned out to be an over current condition at very low rpm. Tweaking some settings fixed that. The Rasmi input filter, and various re-wiring and shielding I did was probably not needed, but in the long run perhaps it will save me from other problems. Thanks, for all the input, -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I have been following this thread somewhat, and have a question, What is the difference between a line reactor and emi input filter? We have a AD GS3 40hp drive in our turning center, and have the same noise problems with the drive, and I am not sure which one to buy, or do I need both? The drive schematic shows putting an emi filter on both sides of the drive, would that help as well? At $272 bucks a piece, I don't want to throw money away, but I do want to get this put to bed, we have been dealing with it for 2 years now, and I am getting tired of it. Thanks Rick On 5/14/2015 9:53 AM, Dave Cole wrote: The Rasmi input filter Take it off and see what happens If that drive is screwing with your keyboard that is on the OUTSIDE of your control cabinet, imagine what kind of RF exposure is on the inside of your control cabinet! Those AD VFDs should also be sold as EMI test generators. ;-) Dave On 5/14/2015 8:53 AM, Tom Easterday wrote: I spent some time with the spectrum analyzer but did’t have much luck in isolating the sink for the noise. I just verified that my VFD does indeed produce a large amount of noise between low kHz and about 10MHz! I did some re-routing of wires and replaced some that weren’t shielded. I ordered some ferrites for the VFD-motor wiring and my computer I/O extension cabling which will be here in a couple days. However, I did find the source of the main problem! It was indeed my keyboard. Not the USB wiring from keyboard to pc, but the keyboard ITSELF is very sensitive to the noise created by the VFD. If I move the keyboard to the very extreme end of it’s (rather long) usb cable the problem disappears completely. 6” closer to the cabinet and noise reappears. Apparently the noise is being interpreted as key presses by the keyboard circuitry. I replaced the new water resistant Logitech keyboard with a very old Apple keyboard I had lying around and no more random characters! I also had a second problem where the VFD would shut down somewhat randomly which I thought was related to this noise as well. That turned out to be an over current condition at very low rpm. Tweaking some settings fixed that. The Rasmi input filter, and various re-wiring and shielding I did was probably not needed, but in the long run perhaps it will save me from other problems. Thanks, for all the input, -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Thanks Rick Lair Superior Roll Turning LLC 399 East Center Street Petersburg MI, 49270 PH: 734-279-1831 FAX: 734-279-1166 www.superiorroll.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On 05/14/2015 07:53 AM, Tom Easterday wrote: I also had a second problem where the VFD would shut down somewhat randomly which I thought was related to this noise as well. That turned out to be an over current condition at very low rpm. Tweaking some settings fixed that. Yes, I had to turn off the electronic motor protection on my mill VFD, as it integrated an overtemp condition when doing rigid tapping. All those reverses added up. Since the Bridgeport motors are made for plug reversing when manual tapping all day long, I figure it can probably handle worse than the VFD could ever deliver. Jon -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On 05/14/2015 09:38 AM, Rick Lair wrote: I have been following this thread somewhat, and have a question, What is the difference between a line reactor and emi input filter? A line reactor may be designed to reduce the 3rd harmonic produced by typical rectifier/capacitor 3-phase loads, and not worry much about higher harmonics. An EMI filter may not do anything for 3rd harmonic, but will be optimized to suppress conducted emissions on anything above a few hudred KHz. We have a AD GS3 40hp drive in our turning center, and have the same noise problems with the drive, and I am not sure which one to buy, or do I need both? The drive schematic shows putting an emi filter on both sides of the drive, would that help as well? Yes, the output side of the VFD is radiating at least as much, if not more, EMI than the input. At $272 bucks a piece, I don't want to throw money away, but I do want to get this put to bed, we have been dealing with it for 2 years now, and I am getting tired of it. You may not need a $272 unit, although for 130 A line current (assuming 240 V, half that for 480 V) they will be a bit expensive. There are shielded cables for VFD to motor connections that are supposed to help. Exactly what is being affected by the EMI? The control itself, or other gear in the plant? If the control of that machine is being affected, then it could be either, or both. if other plant equipment, then if the VFD is in a cabinet directly on the machine, then it sounds mostly like it is coupling through the input to the VFD, so I'd put the money at the input side first. Also, make sure the machine frame is securely grounded to the electrical panel ground. EMI return currents will flow through the ground. if the machine has a plugged-in power cord (Hubbel twist-lock style) then maybe run an additional ground to the outlet box. (Hmmm, 40 Hp machines won't likely be plugged in, even at 480.) You can get into trouble putting EMI filters on the output of the VFD, as this can cause excessive currents that can damage either the filter or the VFD. So, for the output side, use ONLY a filter recommended by the VFD maker. On the input side, you can use any filter that can handle the current draw, so you are not restricted by the VFD maker's recommendations. Jon -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I guess a common mode filter will be good but I have almost only theoretical knowledge and very limited experience. Nicklas Karlsson On Thu, 14 May 2015 10:38:43 -0400 Rick Lair r...@superiorroll.com wrote: I have been following this thread somewhat, and have a question, What is the difference between a line reactor and emi input filter? We have a AD GS3 40hp drive in our turning center, and have the same noise problems with the drive, and I am not sure which one to buy, or do I need both? The drive schematic shows putting an emi filter on both sides of the drive, would that help as well? At $272 bucks a piece, I don't want to throw money away, but I do want to get this put to bed, we have been dealing with it for 2 years now, and I am getting tired of it. Thanks Rick On 5/14/2015 9:53 AM, Dave Cole wrote: The Rasmi input filter Take it off and see what happens If that drive is screwing with your keyboard that is on the OUTSIDE of your control cabinet, imagine what kind of RF exposure is on the inside of your control cabinet! Those AD VFDs should also be sold as EMI test generators. ;-) Dave On 5/14/2015 8:53 AM, Tom Easterday wrote: I spent some time with the spectrum analyzer but did’t have much luck in isolating the sink for the noise. I just verified that my VFD does indeed produce a large amount of noise between low kHz and about 10MHz! I did some re-routing of wires and replaced some that weren’t shielded. I ordered some ferrites for the VFD-motor wiring and my computer I/O extension cabling which will be here in a couple days. However, I did find the source of the main problem! It was indeed my keyboard. Not the USB wiring from keyboard to pc, but the keyboard ITSELF is very sensitive to the noise created by the VFD. If I move the keyboard to the very extreme end of it’s (rather long) usb cable the problem disappears completely. 6” closer to the cabinet and noise reappears. Apparently the noise is being interpreted as key presses by the keyboard circuitry. I replaced the new water resistant Logitech keyboard with a very old Apple keyboard I had lying around and no more random characters! I also had a second problem where the VFD would shut down somewhat randomly which I thought was related to this noise as well. That turned out to be an over current condition at very low rpm. Tweaking some settings fixed that. The Rasmi input filter, and various re-wiring and shielding I did was probably not needed, but in the long run perhaps it will save me from other problems. Thanks, for all the input, -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Thanks Rick Lair Superior Roll Turning LLC 399 East Center Street Petersburg MI, 49270 PH: 734-279-1831 FAX: 734-279-1166 www.superiorroll.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On Thu, 14 May 2015, Karlsson Wang wrote: Date: Thu, 14 May 2015 21:53:05 +0200 From: Karlsson Wang nicklas.karls...@karlssonwang.se Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise I guess a common mode filter will be good but I have almost only theoretical knowledge and very limited experience. Nicklas Karlsson We found that common mode filters (big ferrite bead around U,V,W) on the motor leads help a lot. Otherwise you have ~360V square waves driving the stray wiring and motor capacitance and _nothing_ to limit the peak current of these fast edges driving into this capacitance to ground. This causes huge ground bumping of the VFD ground. A common mode choke limits these peak currents considerably (and is probably built-in in better drives) On Thu, 14 May 2015 10:38:43 -0400 Rick Lair r...@superiorroll.com wrote: I have been following this thread somewhat, and have a question, What is the difference between a line reactor and emi input filter? We have a AD GS3 40hp drive in our turning center, and have the same noise problems with the drive, and I am not sure which one to buy, or do I need both? The drive schematic shows putting an emi filter on both sides of the drive, would that help as well? At $272 bucks a piece, I don't want to throw money away, but I do want to get this put to bed, we have been dealing with it for 2 years now, and I am getting tired of it. Thanks Rick On 5/14/2015 9:53 AM, Dave Cole wrote: The Rasmi input filter Take it off and see what happens If that drive is screwing with your keyboard that is on the OUTSIDE of your control cabinet, imagine what kind of RF exposure is on the inside of your control cabinet! Those AD VFDs should also be sold as EMI test generators. ;-) Dave On 5/14/2015 8:53 AM, Tom Easterday wrote: I spent some time with the spectrum analyzer but did??t have much luck in isolating the sink for the noise. I just verified that my VFD does indeed produce a large amount of noise between low kHz and about 10MHz! I did some re-routing of wires and replaced some that weren??t shielded. I ordered some ferrites for the VFD-motor wiring and my computer I/O extension cabling which will be here in a couple days. However, I did find the source of the main problem! It was indeed my keyboard. Not the USB wiring from keyboard to pc, but the keyboard ITSELF is very sensitive to the noise created by the VFD. If I move the keyboard to the very extreme end of it??s (rather long) usb cable the problem disappears completely. 6?? closer to the cabinet and noise reappears. Apparently the noise is being interpreted as key presses by the keyboard circuitry. I replaced the new water resistant Logitech keyboard with a very old Apple keyboard I had lying around and no more random characters! I also had a second problem where the VFD would shut down somewhat randomly which I thought was related to this noise as well. That turned out to be an over current condition at very low rpm. Tweaking some settings fixed that. The Rasmi input filter, and various re-wiring and shielding I did was probably not needed, but in the long run perhaps it will save me from other problems. Thanks, for all the input, -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Thanks Rick Lair Superior Roll Turning LLC 399 East Center Street Petersburg MI, 49270 PH: 734-279-1831 FAX: 734-279-1166 www.superiorroll.com -- One dashboard for servers and applications across Physical
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I forgot to mention. There is a capacitance between motor cables and protective earth. Then the motor is driven by the VFD it is supplied with square wave voltages at high frequency and at each switching the capacitance is discharged or charged. As impedance at high frequency is far from zero in the power cables the ground will bounce around. If i think correctly both the protective and the rectified power ground will bounce around in opposite directions but I have never measured this. The common mode impedance may be rised by adding a common mode inductur in the loop. Nicklas Karlsson On Thu, 14 May 2015 10:38:43 -0400 Rick Lair r...@superiorroll.com wrote: I have been following this thread somewhat, and have a question, What is the difference between a line reactor and emi input filter? We have a AD GS3 40hp drive in our turning center, and have the same noise problems with the drive, and I am not sure which one to buy, or do I need both? The drive schematic shows putting an emi filter on both sides of the drive, would that help as well? At $272 bucks a piece, I don't want to throw money away, but I do want to get this put to bed, we have been dealing with it for 2 years now, and I am getting tired of it. Thanks Rick On 5/14/2015 9:53 AM, Dave Cole wrote: The Rasmi input filter Take it off and see what happens If that drive is screwing with your keyboard that is on the OUTSIDE of your control cabinet, imagine what kind of RF exposure is on the inside of your control cabinet! Those AD VFDs should also be sold as EMI test generators. ;-) Dave On 5/14/2015 8:53 AM, Tom Easterday wrote: I spent some time with the spectrum analyzer but did’t have much luck in isolating the sink for the noise. I just verified that my VFD does indeed produce a large amount of noise between low kHz and about 10MHz! I did some re-routing of wires and replaced some that weren’t shielded. I ordered some ferrites for the VFD-motor wiring and my computer I/O extension cabling which will be here in a couple days. However, I did find the source of the main problem! It was indeed my keyboard. Not the USB wiring from keyboard to pc, but the keyboard ITSELF is very sensitive to the noise created by the VFD. If I move the keyboard to the very extreme end of it’s (rather long) usb cable the problem disappears completely. 6” closer to the cabinet and noise reappears. Apparently the noise is being interpreted as key presses by the keyboard circuitry. I replaced the new water resistant Logitech keyboard with a very old Apple keyboard I had lying around and no more random characters! I also had a second problem where the VFD would shut down somewhat randomly which I thought was related to this noise as well. That turned out to be an over current condition at very low rpm. Tweaking some settings fixed that. The Rasmi input filter, and various re-wiring and shielding I did was probably not needed, but in the long run perhaps it will save me from other problems. Thanks, for all the input, -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Thanks Rick Lair Superior Roll Turning LLC 399 East Center Street Petersburg MI, 49270 PH: 734-279-1831 FAX: 734-279-1166 www.superiorroll.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight.
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On 5/14/2015 6:53 AM, Tom Easterday wrote: However, I did find the source of the main problem! It was indeed my keyboard. Not the USB wiring from keyboard to pc, but the keyboard ITSELF is very sensitive to the noise created by the VFD. If I move the keyboard to the very extreme end of it’s (rather long) usb cable the problem disappears completely. 6” closer to the cabinet and noise reappears. Apparently the noise is being interpreted as key presses by the keyboard circuitry. I replaced the new water resistant Logitech keyboard with a very old Apple keyboard I had lying around and no more random characters! I also had a second problem where the VFD would shut down somewhat randomly which I thought was related to this noise as well. That turned out to be an over current condition at very low rpm. Tweaking some settings fixed that. Good to know. Apparently Logitech takes the second part of 47 C.F.R. 15.5 (b) literally. ... interference must be accepted that may be caused by the operation of an authorized radio station, by another intentional or unintentional radiator, by industrial, scientific and medical (ISM) equipment, or by an incidental radiator. http://www.gpo.gov/fdsys/pkg/CFR-2014-title47-vol1/xml/CFR-2014-title47-vol1-sec15-5.xml Your VFD is the incidental radiator. I'd be building a metal window screen box around it. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On May 14, 2015, at 4:15 PM, Peter C. Wallace p...@mesanet.com wrote: We found that common mode filters (big ferrite bead around U,V,W) on the motor leads help a lot. Otherwise you have ~360V square waves driving the stray wiring and motor capacitance and _nothing_ to limit the peak current of these fast edges driving into this capacitance to ground. This causes huge ground bumping of the VFD ground. A common mode choke limits these peak currents considerably (and is probably built-in in better drives) The GS2 VFD manual says that if you cannot have a ferrite wrapped on each lead, you can use 4 of them together to enclose the entire motor cable. I don’t have extra wire to do them individually and my wire is a multi-conductor (3 + ground). So I am going to put 4 ferrites together over the whole cable (including ground). I hope that has the same or similar effect. I am wondering if I will see any effect in the amplitude of the generated noise on the spectrum analyzer I have…? -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I don’t think the rule intends that you must react to it, or re-send it! They may have taken it a bit too far ;-) -Tom On May 14, 2015, at 7:51 PM, Gregg Eshelman g_ala...@yahoo.com wrote: On 5/14/2015 6:53 AM, Tom Easterday wrote: However, I did find the source of the main problem! It was indeed my keyboard. Not the USB wiring from keyboard to pc, but the keyboard ITSELF is very sensitive to the noise created by the VFD. If I move the keyboard to the very extreme end of it’s (rather long) usb cable the problem disappears completely. 6” closer to the cabinet and noise reappears. Apparently the noise is being interpreted as key presses by the keyboard circuitry. I replaced the new water resistant Logitech keyboard with a very old Apple keyboard I had lying around and no more random characters! I also had a second problem where the VFD would shut down somewhat randomly which I thought was related to this noise as well. That turned out to be an over current condition at very low rpm. Tweaking some settings fixed that. Good to know. Apparently Logitech takes the second part of 47 C.F.R. 15.5 (b) literally. ... interference must be accepted that may be caused by the operation of an authorized radio station, by another intentional or unintentional radiator, by industrial, scientific and medical (ISM) equipment, or by an incidental radiator. http://www.gpo.gov/fdsys/pkg/CFR-2014-title47-vol1/xml/CFR-2014-title47-vol1-sec15-5.xml Your VFD is the incidental radiator. I'd be building a metal window screen box around it. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I forgot to mention. Automation Direct does allow returns up to 30 days after the purchase, so if you try out the filter and it doesn't work.. Dave On 5/12/2015 9:20 AM, Tom Easterday wrote: Thanks everyone for the great ideas. I have a much fix now. I will let you know what I find. -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I was getting similar symptoms - random stuff happening in Axis, windows popping up, etc. - and it turned out it was just a cheap usb keyboard that started malfunctioning and sending out random keystrokes. I replaced the keyboard and everything is fine... - Claude On Wed, May 13, 2015 at 6:54 AM, Dave Cole linuxcncro...@gmail.com wrote: I forgot to mention. Automation Direct does allow returns up to 30 days after the purchase, so if you try out the filter and it doesn't work.. Dave On 5/12/2015 9:20 AM, Tom Easterday wrote: Thanks everyone for the great ideas. I have a much fix now. I will let you know what I find. -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I had suspected EMI as the cause of these symptoms as well, until last night when things got really bad. The spindle and axis motors were NOT running. I was simply trying to set up for a run. Most of the behavior seemed like mouse clicks into random locations in the Manual Control window of Axis (including multiple very disturbing activations of the spindle start button). I had these symptoms with a different USB mouse as well. I will change out the mouse again, but I smell a rat... --Tim - Original Message - From: Claude Zervas cla...@utlco.com To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Sent: Wednesday, May 13, 2015 11:19:21 AM Subject: Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise I was getting similar symptoms - random stuff happening in Axis, windows popping up, etc. - and it turned out it was just a cheap usb keyboard that started malfunctioning and sending out random keystrokes. I replaced the keyboard and everything is fine... - Claude On Wed, May 13, 2015 at 6:54 AM, Dave Cole linuxcncro...@gmail.com wrote: I forgot to mention. Automation Direct does allow returns up to 30 days after the purchase, so if you try out the filter and it doesn't work.. Dave On 5/12/2015 9:20 AM, Tom Easterday wrote: Thanks everyone for the great ideas. I have a much fix now. I will let you know what I find. -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
Grounding. Power ground must be separated from small signal ground. The VFD also generate a common mode voltage and unless a common mode inductor is added to increase common mode impedance there will be a high frequency current flowing thru the protected earth wire which in combination with the protected earth cable impedance at high frequency will make it bounce around. I know about two paths for the common mode voltage: capcitance inside the VFD to protected earth and between motor cables and protected earth. Nicklas Karlsson On Mon, 11 May 2015 21:00:39 -0400 Tom Easterday tom-...@bgp.nu wrote: Early on we made a decision to put our VFD into the same cabinet as the rest of the electronics on a lathe retrofit - I originally had two separate cabinets, one for power with vfd and one for electronics. This was to save space and bring the size of the cabinet on the machine down to a more reasonable size so it might fit through doors, etc. In retrospect, perhaps that was a bad idea. But here we are trying to address VFD induced noise problems. The cabinet is shown in a picture here: https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ There is actually more wiring completed now then what is shown in the picture but you get the idea. After having read about folks often using Rasmi input power filters to solve noise issues I purchased one from ebay and installed it today. It didn’t help, and may have actually made the problem worse. I installed it very close to the VFD input power terminals as recommended. When I run the spindle motor on it’s lowest RPM I hear a high pitched whine (at the motor) and strange things begin to happen in Axis. Windows pop up, perhaps a homing window, perhaps a touch off, perhaps Axis switches to MDI mode, sometimes it turns the machine off, sometimes it turns the machine off but the spindle keeps moving! Sometimes the VFD shuts off and displays oL 1” on the screen. So now I want to understand how this noise is getting into the PC. I first thought it was because the keyboard, mouse, and video cables ran past the VFD in the cabinet and noise was being induced on the keyboard cable. So in trying to isolate where the issue was I disconnected those cables and ran them far away from the VFD. No help.. I then wondered if it was coming in the AC power to the PC, so I rerouted the PC power to a completely different outlet outside of the cabinet. No help. I then rerouted the network and video cables to get those away from the VFD, no help again. Even with the door open (as you see in the picture) I have noise. The only thing connecting the PC to the rest of the system is the parallel cable which is about 12” long that connects to the Mesa 7i85s card (and again, that is at the other end of my cabinet from the VFD). Today I borrowed a friend’s 0-1Ghz spectrum analyzer to see if I can find the source/frequency of the noise and/or where it might be getting to the PC. I will start playing with that tomorrow. I am wondering if anyone has any ideas of where i can look, or what I can do? -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I'm not the strongest electrically, but when I've run into noise issues, it was either we did something obvious and we were able to fix it (like in the non-grounded lathe example from Marius Liebenberg) or we never found the problem. We put on all kinds of ferrite torrids and inline filters and they didn't do squat. While they may work, I'm skeptical. I think you said your issue was windows start to open and you get weird behavior on the screen, it seems to be mouse, keyboard, or pc noise. I see a large 'wall wart' power supply that I'm assuming is powering the PC? Maybe I missed the other PC power supply, but those wall warts are usually un-grounded, so maybe try a standard PC power supply w/ a ground on the power cord and to the PC. Another thing to try might be how you have the Mesa card powered, I'm not sure what Mesa board you have, but the 7i77 has jumpers for 5Vdc and you can power from the PC or externally. Maybe you've got noise on that 5V rail back through the PC? Lastly, running the mouse or keyboard cable near a power cable, especially a noisy one, could cause what you're seeing. I think you tried this one already. Mark -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
One more thing... I'd put the cover on that M350 computer chassis. That will help keep RF out of the computer. Dave On 5/11/2015 9:00 PM, Tom Easterday wrote: Early on we made a decision to put our VFD into the same cabinet as the rest of the electronics on a lathe retrofit - I originally had two separate cabinets, one for power with vfd and one for electronics. This was to save space and bring the size of the cabinet on the machine down to a more reasonable size so it might fit through doors, etc. In retrospect, perhaps that was a bad idea. But here we are trying to address VFD induced noise problems. The cabinet is shown in a picture here: https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ There is actually more wiring completed now then what is shown in the picture but you get the idea. After having read about folks often using Rasmi input power filters to solve noise issues I purchased one from ebay and installed it today. It didn’t help, and may have actually made the problem worse. I installed it very close to the VFD input power terminals as recommended. When I run the spindle motor on it’s lowest RPM I hear a high pitched whine (at the motor) and strange things begin to happen in Axis. Windows pop up, perhaps a homing window, perhaps a touch off, perhaps Axis switches to MDI mode, sometimes it turns the machine off, sometimes it turns the machine off but the spindle keeps moving! Sometimes the VFD shuts off and displays oL 1” on the screen. So now I want to understand how this noise is getting into the PC. I first thought it was because the keyboard, mouse, and video cables ran past the VFD in the cabinet and noise was being induced on the keyboard cable. So in trying to isolate where the issue was I disconnected those cables and ran them far away from the VFD. No help.. I then wondered if it was coming in the AC power to the PC, so I rerouted the PC power to a completely different outlet outside of the cabinet. No help. I then rerouted the network and video cables to get those away from the VFD, no help again. Even with the door open (as you see in the picture) I have noise. The only thing connecting the PC to the rest of the system is the parallel cable which is about 12” long that connects to the Mesa 7i85s card (and again, that is at the other end of my cabinet from the VFD). Today I borrowed a friend’s 0-1Ghz spectrum analyzer to see if I can find the source/frequency of the noise and/or where it might be getting to the PC. I will start playing with that tomorrow. I am wondering if anyone has any ideas of where i can look, or what I can do? -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On 11.05.15 23:14, Tom Easterday wrote: I will do that tomorrow. I wonder if using this tape to shield unshielded wire, like my VFD to motor cable, would work….? http://www.cesco.com/b2c/product/9770?utm_source=googleutm_medium=cpcutm_campaign=shoppingscid=scplp2640202gclid=CMTdkaSbu8UCFZeDaQodlRgAHQ That or copper tape can be used for shielding, but still forms a coiled inductor back to the cable ends, unless contact between turns is very good. Can you run two tape lengths longitudinally, overlapping their edges around the cable diameter, and stitching them into a tube with frequent solder joints? Minimum impedance, at RF, back to your star earth (from one end only) has to be good, after shutting it in. Or, do you have some Al or Cu tubing in the junkbox, that you can bend after pushing the cable through? If it's to hand, it's something you can do without waiting for deliveries, and should work at least as well. If it's primarily magnetic coupling, then steel tubing might be better. Experimenting with a (mostly) closed steel box around the computer can help determine that. The power radiated is proportional to the open area between the two power conductors. If they are twisted, e.g. one turn per inch, then that is minimised, and there is less work for shielding to do. My mini-ITX mobo is powered by a picoPSU, so can run off a 12v battery. Thus isolating power entirely, and disconnecting the parport or other I/O would allow checking whether Axis still plays up - proving that it is radiated EMI. That may be hard to do there. It'll be very interesting to hear what finally cures it. Erik -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On 12 May 2015 at 02:00, Tom Easterday tom-...@bgp.nu wrote: I am wondering if anyone has any ideas of where i can look, or what I can do? I had a similar (but much less serious) problem and one of the things I did was to take the outgoing motor cables through a common-mode choke. (ie all three wires go through the same ferrite toroid a few times before continuing to the motor. The idea of this is that it slows the rise-rate of the VFD chopper pulses and removes some of the high-frequency content. I suspect it is not a good idea to over-do this. I also don't know it if helped, as I fitted an input filter at the same time. It is interesting that the Mesa 8i20s I have all came with a clamp-on toroid for the output wires supplied. (And the output toroid suggestion came from PCW) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
Thanks everyone for the great ideas. I have a much fix now. I will let you know what I find. -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I have had very good luck with drive input filters sold by Automation Direct.On the box it says Delta Electronics Model 20DRT1W3S. Here it is. http://www.automationdirect.com/adc/Shopping/Catalog/Drives/AC_Drive_%28VFD%29_Spare_Parts_-a-_Accessories/GS_EMI_-z-_RF_Filters/EMI_-z-_RF_Filters_%28All_GS_Drives%29/20DRT1W3S This is a single phase in/out filter I installed on some Teco servo drives that were scrambling the Mesa boards on an analog servo application in a panel quite a bit larger than yours. That black SO cord running from the top of the drive to the contactor (I think) is an excellent broadcast antenna that will induce voltages into other circuits. I mounted the filter just above the drive so I had short leads from the filter to the drive.All problems vanished. Can you run your motor leads in sealtite? Get the metallic variety of course. That should also work to shield your motor leads. Automation Direct also sells output chokes which will cut down on noise on the motor leads. Dave On 5/11/2015 9:00 PM, Tom Easterday wrote: Early on we made a decision to put our VFD into the same cabinet as the rest of the electronics on a lathe retrofit - I originally had two separate cabinets, one for power with vfd and one for electronics. This was to save space and bring the size of the cabinet on the machine down to a more reasonable size so it might fit through doors, etc. In retrospect, perhaps that was a bad idea. But here we are trying to address VFD induced noise problems. The cabinet is shown in a picture here: https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ There is actually more wiring completed now then what is shown in the picture but you get the idea. After having read about folks often using Rasmi input power filters to solve noise issues I purchased one from ebay and installed it today. It didn’t help, and may have actually made the problem worse. I installed it very close to the VFD input power terminals as recommended. When I run the spindle motor on it’s lowest RPM I hear a high pitched whine (at the motor) and strange things begin to happen in Axis. Windows pop up, perhaps a homing window, perhaps a touch off, perhaps Axis switches to MDI mode, sometimes it turns the machine off, sometimes it turns the machine off but the spindle keeps moving! Sometimes the VFD shuts off and displays oL 1” on the screen. So now I want to understand how this noise is getting into the PC. I first thought it was because the keyboard, mouse, and video cables ran past the VFD in the cabinet and noise was being induced on the keyboard cable. So in trying to isolate where the issue was I disconnected those cables and ran them far away from the VFD. No help.. I then wondered if it was coming in the AC power to the PC, so I rerouted the PC power to a completely different outlet outside of the cabinet. No help. I then rerouted the network and video cables to get those away from the VFD, no help again. Even with the door open (as you see in the picture) I have noise. The only thing connecting the PC to the rest of the system is the parallel cable which is about 12” long that connects to the Mesa 7i85s card (and again, that is at the other end of my cabinet from the VFD). Today I borrowed a friend’s 0-1Ghz spectrum analyzer to see if I can find the source/frequency of the noise and/or where it might be getting to the PC. I will start playing with that tomorrow. I am wondering if anyone has any ideas of where i can look, or what I can do? -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
Early on we made a decision to put our VFD into the same cabinet as the rest of the electronics on a lathe retrofit - I originally had two separate cabinets, one for power with vfd and one for electronics. This was to save space and bring the size of the cabinet on the machine down to a more reasonable size so it might fit through doors, etc. In retrospect, perhaps that was a bad idea. But here we are trying to address VFD induced noise problems. The cabinet is shown in a picture here: https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ There is actually more wiring completed now then what is shown in the picture but you get the idea. After having read about folks often using Rasmi input power filters to solve noise issues I purchased one from ebay and installed it today. It didn’t help, and may have actually made the problem worse. I installed it very close to the VFD input power terminals as recommended. When I run the spindle motor on it’s lowest RPM I hear a high pitched whine (at the motor) and strange things begin to happen in Axis. Windows pop up, perhaps a homing window, perhaps a touch off, perhaps Axis switches to MDI mode, sometimes it turns the machine off, sometimes it turns the machine off but the spindle keeps moving! Sometimes the VFD shuts off and displays oL 1” on the screen. So now I want to understand how this noise is getting into the PC. I first thought it was because the keyboard, mouse, and video cables ran past the VFD in the cabinet and noise was being induced on the keyboard cable. So in trying to isolate where the issue was I disconnected those cables and ran them far away from the VFD. No help.. I then wondered if it was coming in the AC power to the PC, so I rerouted the PC power to a completely different outlet outside of the cabinet. No help. I then rerouted the network and video cables to get those away from the VFD, no help again. Even with the door open (as you see in the picture) I have noise. The only thing connecting the PC to the rest of the system is the parallel cable which is about 12” long that connects to the Mesa 7i85s card (and again, that is at the other end of my cabinet from the VFD). Today I borrowed a friend’s 0-1Ghz spectrum analyzer to see if I can find the source/frequency of the noise and/or where it might be getting to the PC. I will start playing with that tomorrow. I am wondering if anyone has any ideas of where i can look, or what I can do? -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
I'm sorry to hear that the Rasmi filter didn't help your noise problems. I bought four of them, and I've installed the first one but am 1-3 days away from finally installing that electrical panel and testing the electronics. Without the Rasmi filter, my CNC router has some noise on the VGA monitor. Sometimes it's barely noticeable, and sometimes it causes a lot of screen flicker. It's VFD frequency (spindle speed) specific. Occasionally, it will blank the screen, which makes controlling the CNC router interesting. I tried clamp on ferrite toroids on the VGA and monitor power cables and that helped a little. The big problem is the way I ran several feet of the monitor cables adjacent to the spindle motor cable. I knew better, but hoped the motor cable shielding would be sufficient. I bought better quality double shielded VGA cable but haven't tried that yet. I should rerun the spindle motor cable far away from any data cables. The Rasmi filter is used to filter conducted noise. It attenuates the electrical noise that might be conducted on the incoming power lines. The Rasmi filter does nothing to attenuate radiated noise that's broadcast by the VFD and the spindle motor cable. This type of noise is analogous to a radio signal that's transmitted through the air, as opposed to being conducted on wires. I suspect radiated noise might be a lot of your problem. The spindle motor cable is a transmitting antenna. All of those other wires in the panel are receiving antennas. Good wiring practices can help, as you've already mentioned. I route power cables in one wireway and data cables in other wireways. It's a nonlinear world, so when a data cable needs to cross a power cable, have them cross at 90 degree angles and don't run them adjacent to each other. Use shielded cable. Shielded spindle motor cable will help prevent the VFD from transmitting radiated noise. Shielded cable for sensitive data signals will help prevent them from receiving the radiated noise signals. Shielding the noise source and the sensitive signals fights the noise at both ends. Keep as much distance as possible between high current lines (particularly the spindle motor cable between the VFD and spindle motor as it has some high frequency switching noise that radiates very well). Distance is your friend. The electromagnetic coupling is in inverse proportion to the square of the distance between the receiver and transmitter. Twice as close results in four times the noise. Four times as close gets you sixteen times as much noise. Shielded twisted pair for data cables (like Cat5 ethernet cable) is particularly noise immune because the shield blocks a lot of the radiated noise, and the noise that makes it through is greatly attenuated by twisting the cable which greatly reduces the common mode noise in those lines. Ground the cable shield at one end only. Usually, the shield is terminated at the source. In the case of the spindle motor cable, I'd ground the shield in the electrical panel next to the VFD. For most applications, I like a star grounding configuration where all of the grounds terminate at one common grounding post. Scrape off any paint and use a star washer to bite into the metal and tighten it enough to make a good gas proof electrical connection that won't corrode in a year or so and cause a high impedance path to ground. A single ground point prevents current loops, where there is a current flowing between two or more ground points. In some special circumstances, you might have better results with a power ground and a data ground, or an analog ground and a digital ground. With two completely separate ground systems, the low voltage electronics won't be subjected to a few volts of ground float noise from a noisy power device like a VFD. If the two subsystems need to have a common reference voltage, the two ground systems can be connected by a resistor (typically 1K to 100K) and/or an RF choke to allow the common voltages of both subsystems to float to the same voltage while attenuating AC noise. Pretty panel wiring is usually less noisy, particularly where radiated noise is concerned. I hope that helps. Good luck slaying the noise gremlins. On 05/11/2015 09:00 PM, Tom Easterday wrote: Early on we made a decision to put our VFD into the same cabinet as the rest of the electronics on a lathe retrofit - I originally had two separate cabinets, one for power with vfd and one for electronics. This was to save space and bring the size of the cabinet on the machine down to a more reasonable size so it might fit through doors, etc. In retrospect, perhaps that was a bad idea. But here we are trying to address VFD induced noise problems. The cabinet is shown in a picture here: https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On 05/11/2015 06:00 PM, Tom Easterday wrote: Early on we made a decision to put our VFD into the same cabinet as the rest of the electronics on a lathe retrofit - I originally had two separate cabinets, one for power with vfd and one for electronics. This was to save space and bring the size of the cabinet on the machine down to a more reasonable size so it might fit through doors, etc. In retrospect, perhaps that was a bad idea. But here we are trying to address VFD induced noise problems. The cabinet is shown in a picture here: https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ Another thing, put the outer case back on the computer you have mounted to the door, or cover the large open holes with solid sheet metal or screen. That's as much to keep noise generated by the computer in as it is to keep interference out. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
On May 11, 2015, at 10:49 PM, Gregg Eshelman g_ala...@yahoo.com wrote: Another thing, put the outer case back on the computer you have mounted to the door, or cover the large open holes with solid sheet metal or screen. That's as much to keep noise generated by the computer in as it is to keep interference out. I will do that tomorrow. I wonder if using this tape to shield unshielded wire, like my VFD to motor cable, would work….? http://www.cesco.com/b2c/product/9770?utm_source=googleutm_medium=cpcutm_campaign=shoppingscid=scplp2640202gclid=CMTdkaSbu8UCFZeDaQodlRgAHQ http://www.cesco.com/b2c/product/9770?utm_source=googleutm_medium=cpcutm_campaign=shoppingscid=scplp2640202gclid=CMTdkaSbu8UCFZeDaQodlRgAHQ -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
Tom, Hard to tell from the picture but I would make sure that ground is properly connected in star configuration, i.e. there is only one ground point [1] in the cabinet and the CNC machine. I suspect you get some ground currents somewhere which possibly cause enough noise to mess up your VFD. [1] ground could be a copper bar with enough holes to attach all ground wires from all cables, CNC chassis, and power filter to it. Connect ground wire to the door itself and whatever is mounted on it as well. It might be worthwhile to add ferrite toroids on critical (analog) lines including parallel cable; see https://en.wikipedia.org/wiki/Toroidal_inductors_and_transformers On 05/11/2015 06:00 PM, Tom Easterday wrote: Early on we made a decision to put our VFD into the same cabinet as the rest of the electronics on a lathe retrofit - I originally had two separate cabinets, one for power with vfd and one for electronics. This was to save space and bring the size of the cabinet on the machine down to a more reasonable size so it might fit through doors, etc. In retrospect, perhaps that was a bad idea. But here we are trying to address VFD induced noise problems. The cabinet is shown in a picture here: https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ https://www.flickr.com/photos/37438950@N00/17219261571/in/album-72157651167328249/ There is actually more wiring completed now then what is shown in the picture but you get the idea. After having read about folks often using Rasmi input power filters to solve noise issues I purchased one from ebay and installed it today. It didn’t help, and may have actually made the problem worse. I installed it very close to the VFD input power terminals as recommended. When I run the spindle motor on it’s lowest RPM I hear a high pitched whine (at the motor) and strange things begin to happen in Axis. Windows pop up, perhaps a homing window, perhaps a touch off, perhaps Axis switches to MDI mode, sometimes it turns the machine off, sometimes it turns the machine off but the spindle keeps moving! Sometimes the VFD shuts off and displays oL 1” on the screen. So now I want to understand how this noise is getting into the PC. I first thought it was because the keyboard, mouse, and video cables ran past the VFD in the cabinet and noise was being induced on the keyboard cable. So in trying to isolate where the issue was I disconnected those cables and ran them far away from the VFD. No help.. I then wondered if it was coming in the AC power to the PC, so I rerouted the PC power to a completely different outlet outside of the cabinet. No help. I then rerouted the network and video cables to get those away from the VFD, no help again. Even with the door open (as you see in the picture) I have noise. The only thing connecting the PC to the rest of the system is the parallel cable which is about 12” long that connects to the Mesa 7i85s card (and again, that is at the other end of my cabinet from the VFD). Today I borrowed a friend’s 0-1Ghz spectrum analyzer to see if I can find the source/frequency of the noise and/or where it migh t be getting to the PC. I will start playing with that tomorrow. I am wondering if anyone has any ideas of where i can look, or what I can do? -Tom -- Rafael -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
Either move the VFD to its own enclosure or isolate it with sheet metal and metal screening, grounded to the enclosure. That will block RFI/EMI radiating directly from the VFD. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
Thanks for all the info Bruce! I suspect you are right that it is radiated noise. I should probably start with the outbound motor wire from the VFD. It is about 5 ft. long and not shielded. There are also a couple other cables I can shield as well that current aren’t. -Tom On May 11, 2015, at 10:05 PM, Bruce Layne linux...@thinkingdevices.com wrote: I'm sorry to hear that the Rasmi filter didn't help your noise problems. I bought four of them, and I've installed the first one but am 1-3 days away from finally installing that electrical panel and testing the electronics. Without the Rasmi filter, my CNC router has some noise on the VGA monitor. Sometimes it's barely noticeable, and sometimes it causes a lot of screen flicker. It's VFD frequency (spindle speed) specific. Occasionally, it will blank the screen, which makes controlling the CNC router interesting. I tried clamp on ferrite toroids on the VGA and monitor power cables and that helped a little. The big problem is the way I ran several feet of the monitor cables adjacent to the spindle motor cable. I knew better, but hoped the motor cable shielding would be sufficient. I bought better quality double shielded VGA cable but haven't tried that yet. I should rerun the spindle motor cable far away from any data cables. The Rasmi filter is used to filter conducted noise. It attenuates the electrical noise that might be conducted on the incoming power lines. The Rasmi filter does nothing to attenuate radiated noise that's broadcast by the VFD and the spindle motor cable. This type of noise is analogous to a radio signal that's transmitted through the air, as opposed to being conducted on wires. I suspect radiated noise might be a lot of your problem. The spindle motor cable is a transmitting antenna. All of those other wires in the panel are receiving antennas. Good wiring practices can help, as you've already mentioned. I route power cables in one wireway and data cables in other wireways. It's a nonlinear world, so when a data cable needs to cross a power cable, have them cross at 90 degree angles and don't run them adjacent to each other. Use shielded cable. Shielded spindle motor cable will help prevent the VFD from transmitting radiated noise. Shielded cable for sensitive data signals will help prevent them from receiving the radiated noise signals. Shielding the noise source and the sensitive signals fights the noise at both ends. Keep as much distance as possible between high current lines (particularly the spindle motor cable between the VFD and spindle motor as it has some high frequency switching noise that radiates very well). Distance is your friend. The electromagnetic coupling is in inverse proportion to the square of the distance between the receiver and transmitter. Twice as close results in four times the noise. Four times as close gets you sixteen times as much noise. Shielded twisted pair for data cables (like Cat5 ethernet cable) is particularly noise immune because the shield blocks a lot of the radiated noise, and the noise that makes it through is greatly attenuated by twisting the cable which greatly reduces the common mode noise in those lines. Ground the cable shield at one end only. Usually, the shield is terminated at the source. In the case of the spindle motor cable, I'd ground the shield in the electrical panel next to the VFD. For most applications, I like a star grounding configuration where all of the grounds terminate at one common grounding post. Scrape off any paint and use a star washer to bite into the metal and tighten it enough to make a good gas proof electrical connection that won't corrode in a year or so and cause a high impedance path to ground. A single ground point prevents current loops, where there is a current flowing between two or more ground points. In some special circumstances, you might have better results with a power ground and a data ground, or an analog ground and a digital ground. With two completely separate ground systems, the low voltage electronics won't be subjected to a few volts of ground float noise from a noisy power device like a VFD. If the two subsystems need to have a common reference voltage, the two ground systems can be connected by a resistor (typically 1K to 100K) and/or an RF choke to allow the common voltages of both subsystems to float to the same voltage while attenuating AC noise. Pretty panel wiring is usually less noisy, particularly where radiated noise is concerned. I hope that helps. Good luck slaying the noise gremlins. -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you
Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise
Replacing the unshielded spindle motor cable with a shielded cable and grounding the shield in the electrical panel is probably going to yield the maximum bang for the buck. Your DIN rail mounted ground terminals in the bottom of your panel are a good single point ground for a star configured grounding scheme, IMO. The only hassle might be getting the shield from the VFD cable down there. I think you were smart to put the VFD on the right side of the electrical panel and the PC on the left side. As I previously mentioned, with radiated noise, distance is your friend. If you're getting noise inside the PC, you might want to put a cover on the PC enclosure. My CNC panels use bare motherboards mounted to the subpanel, but some shielding is good. BTW - Electromagnetic radiated noise has an electric field and a magnetic field. Sometimes you'll seem to have more of one than another. Aluminum will block an electric field but isn't as good at attenuating a magnetic field. A steel panel attenuates magnetic fields better. Mu metal is the best electromagnetic shielding but typically isn't practical for this sort of problem. You can use a couple of small C clamps to hold sheet metal over an open chassis hole to do a real world test to determine how effective it'll be before spending time fabricating a cover only to learn that it doesn't reduce the noise. I also liked your comment about using a spectrum analyzer to quantify the noise. Noise problems can be counter intuitive and it's difficult to fix a problem if you don't know what it is, or even where it is. If good wiring practices result in intolerable noise, I might sprinkle a few magic ferrite beans around in a blind attempt to fix a specific problem, but if that doesn't work I'll quickly proceed to step 2, which involves the digital storage oscilloscope. /“When you can measure what you are speaking about, and express it in numbers, you know something about it, when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts advanced to the stage of science.”// // // - Lord Kelvin// / On 05/11/2015 10:44 PM, Tom Easterday wrote: Thanks for all the info Bruce! I suspect you are right that it is radiated noise. I should probably start with the outbound motor wire from the VFD. It is about 5 ft. long and not shielded. There are also a couple other cables I can shield as well that current aren’t. -Tom -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
