On 2014-11-26 22:12, Peter C. Wallace wrote: > On Wed, 26 Nov 2014, Karlsson & Wang wrote: > >> Date: Wed, 26 Nov 2014 20:53:56 +0100 >> From: Karlsson & Wang <[email protected]> >> Reply-To: "Enhanced Machine Controller (EMC)" >> <[email protected]> >> To: "Enhanced Machine Controller (EMC)" <[email protected]> >> Subject: Re: [Emc-users] EMC communication problem then motor start >> >> The switching is very fast because gate transistor is 10 ohm so I will >> increase as an intermediate solution. The problem is however still >> interesting because it is so common. >> >> Nicklas Karlsson >> > One option that helps a lot on PWM drives is a common mode choke on the PWM > outputs (a large ferrite bead on the 2 (DC) or 3 (AC) motor wires). One major > problem with PWM outputs without slew rate limiting driving motor windings is > the nearly unlimited current spike that happens at switching time because > of the very fast slew rate PWM signal driving into wiring/ motor winding to > ground capacitance. > Would you place the bead closer to the drive or closer to the motor?
> > >> >> On Wed, 26 Nov 2014 19:34:44 +0000 >> David Armstrong <[email protected]> wrote: >> >>> i normaly make sure that all low voltage wiring is sheilded and watch for >>> ground loops and vfd inputs are via filters and Balance transformers , >>> ethernet coms are usually problem free so long as you use good cables and >>> not the cheap Aluminium wire ones as they are using balanced paired cores >>> , in 2 real major projects i ended up passing the low volt cables inside >>> sheilding cut from ur67 coax >>> >>> >>> >>> On 26 November 2014 at 18:40, Karlsson & Wang < >>> [email protected]> wrote: >>> >>>> I have tried with USB isolator made with Icoupler devices from analog >>>> devices on other products without luck. I am using ethernet which I think >>>> have a isolation transformer. I do not think there are any tolerances for >>>> missed packets right now. For serial communication I have tried opto >>>> couplers without with some improvement. I have also tried isolation devices >>>> from I think Texas instruments made from differential drive over two >>>> capacitors and they are great but I do not think I could use them for >>>> 100Mbit ethernet. >>>> >>>> I will increase tolerance for missed packets to be able to measure >>>> percentage of lost packets, it is not perfect but better than nothing. I >>>> will also add a common mode inductor and maybe a shielded cable. >>>> >>>> I have encountered the problem on several products so it is not isolated >>>> to just this one I built myself. >>>> >>>> >>>> Nicklas Karlsson >>>> >>>> >>>> >>>> >>>> On Wed, 26 Nov 2014 19:28:25 +0200 >>>> Marius Liebenberg <[email protected]> wrote: >>>> >>>>> I have had many problems with USB communications with motors and plasma. >>>>> You can overcome these by putting an electrically isolated barrier in >>>>> the usb line. There are some chips from Linear (LTM2448) that will do >>>>> just that. The equipment on either end cannot be connected to the same >>>>> ground or supply if you go this route. >>>>> >>>>> On 2014-11-26 19:07, Karlsson & Wang wrote: >>>>>> PWM is great for efficient motor but unfortunately it is also very >>>> good at disturbing digital communication. Do anybody had any problems with >>>> the communication errors then motor start? >>>>>> Nicklas Karlsson >>>>>> >>>>>> >>>> ------------------------------------------------------------------------------ >>>>>> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server >>>>>> from Actuate! Instantly Supercharge Your Business Reports and >>>> Dashboards >>>>>> with Interactivity, Sharing, Native Excel Exports, App Integration & >>>> more >>>>>> Get technology previously reserved for billion-dollar corporations, >>>> FREE >>>> http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk >>>>>> _______________________________________________ >>>>>> Emc-users mailing list >>>>>> [email protected] >>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>>>> >>>>> -- >>>>> >>>>> Regards /Groete >>>>> >>>>> Marius D. Liebenberg >>>>> +27 82 698 3251 >>>>> +27 12 743 6064 >>>>> QQ 1767394877 >>>>> >>>>> >>>>> >>>> ------------------------------------------------------------------------------ >>>>> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server >>>>> from Actuate! Instantly Supercharge Your Business Reports and Dashboards >>>>> with Interactivity, Sharing, Native Excel Exports, App Integration & more >>>>> Get technology previously reserved for billion-dollar corporations, FREE >>>>> >>>> http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk >>>>> _______________________________________________ >>>>> Emc-users mailing list >>>>> [email protected] >>>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>> >>>> ------------------------------------------------------------------------------ >>>> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server >>>> from Actuate! Instantly Supercharge Your Business Reports and Dashboards >>>> with Interactivity, Sharing, Native Excel Exports, App Integration & more >>>> Get technology previously reserved for billion-dollar corporations, FREE >>>> >>>> http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk >>>> _______________________________________________ >>>> Emc-users mailing list >>>> [email protected] >>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>> >>> ------------------------------------------------------------------------------ >>> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server >>> from Actuate! Instantly Supercharge Your Business Reports and Dashboards >>> with Interactivity, Sharing, Native Excel Exports, App Integration & more >>> Get technology previously reserved for billion-dollar corporations, FREE >>> http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk >>> _______________________________________________ >>> Emc-users mailing list >>> [email protected] >>> https://lists.sourceforge.net/lists/listinfo/emc-users >> ------------------------------------------------------------------------------ >> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server >> from Actuate! Instantly Supercharge Your Business Reports and Dashboards >> with Interactivity, Sharing, Native Excel Exports, App Integration & more >> Get technology previously reserved for billion-dollar corporations, FREE >> http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk >> _______________________________________________ >> Emc-users mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > Peter Wallace > Mesa Electronics > > (\__/) > (='.'=) This is Bunny. Copy and paste bunny into your > (")_(") signature to help him gain world domination. > > > ------------------------------------------------------------------------------ > Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server > from Actuate! Instantly Supercharge Your Business Reports and Dashboards > with Interactivity, Sharing, Native Excel Exports, App Integration & more > Get technology previously reserved for billion-dollar corporations, FREE > http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Regards /Groete Marius D. Liebenberg +27 82 698 3251 +27 12 743 6064 QQ 1767394877 ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
