EN 61000-4-5 Surge on 24VAC equipment
"I see your point, but as I understand it, only if the power pack is made available with the apparatus to the end user, i.e. a system. This is up to the manufacturer to define." 1. Many 24 VAC products are shipped with a separate 230/24VAC transformer unit that plugs into the mains. In this case, Surge testing is performed on the 230 Volt side of the transformer. 2. Occasionally, products with a 24 VAC input are marketed without a transformer. Example: small surveillance cameras. Several of these cameras are often installed in a factory or office, and the 24 VAC is daisy-chained from a single 230/24 VAC transformer. In this situation the EMC Laboratory will often recommend that the camera manufacturer provide a "typical" transformer that might be chosen by the end user. Surge testing is then performed on the 230 Volt side of this "representative" transformer. And of course, the Test Report will clearly state the rationale for this arrangement. Jim Ericson Acme Testing Company --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: noise figure
I may not have been as clear as desirable in the line where I say, "N = -67 dBuV/Hz." That is based on a noise figure numerically equal to one, or 0 dB. To give a numerical example, say it is a radiated measurement where you have determined that the limit is 40 dBuV/m (30 - 88 MHz), the antenna factor is 13 dB/m with a 3 dB pad at antenna to reduce mismatch, and cable loss is negligible. If we desire that the noise floor of the receiver/analyzer be 6 dB below the limit, then N (dBuV) = 40 dBuV/m - 13 dB/m - 3 dB - 6 dB = 18 dBuV With a perfect noise figure (0 dB) N = -67 dB uV/Hz + 10 * log (120,000 Hz) = -16 dBuV That means that your analyzer/receiver noise figure can be no greater than 18 dBuV - (-16 dBuV) = 34 dB. This is easily achievable with a receiver. You might be right on the edge with an HP8566 spectrum analyzer with no video filtering. The HP8566 has a 29 dB noise figure with full video filtering. -- >From: "Ken Javor" >To: "KC CHAN [PDD]" , emc-p...@majordomo.ieee.org >Subject: Re: noise figure >Date: Sat, Dec 22, 2001, 3:59 AM > > > Take the limit you are measuring to, and subtract the transducer factor and > any cable losses. That yields the receiver signal in dBuV which corresponds > to a spec level signal. Subtract off a factor for how much you want the > receiver noise floor to be below the spec level, typically 6 dB. Call this > level N. Then basic statistical thermodynamic theory says that N = kTBF, > where K is Boltzman's constant (the ideal gas law constant divided by > Avogadro's number), T is absolute temperature in Kelvin, B is bandwidth in > Hertz, and F is the noise figure. At room temperature, 25 degrees Celsius > or 298 Kelvin, N = -67 dBuV/Hz, with the bandwidth dependency going as 10 > log (BW) because the basic equation is for noise power. Now given your > bandwidth, say 120 kHz, you can solve for the necessary noise figure. If > your receiver/analyzer noise figure is higher than that needed, there is > another simple equation that will allow you to specify a preamp that will > allow the combination measurement system to perform as required. > > -- >>From: "KC CHAN [PDD]" >>To: >>Subject: noise figure >>Date: Fri, Dec 21, 2001, 6:42 PM >> > >> >> Hi all >> >> It may not be purely EMC question, actually it is RF related, but I am sure >> the experts here can answer my questions. >> >> We all know that we need to have a pre-amp. that is as lower noise figure >> as possible, but how low it is enough or how it is related to the noise >> floor viewed by a receiver or spectrum analyzer. >> >> Thank you >> KC Chan >> >> >> --- >> This message is from the IEEE EMC Society Product Safety >> Technical Committee emc-pstc discussion list. >> >> Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ >> >> To cancel your subscription, send mail to: >> majord...@ieee.org >> with the single line: >> unsubscribe emc-pstc >> >> For help, send mail to the list administrators: >> Michael Garretson:pstc_ad...@garretson.org >> Dave Healddavehe...@mediaone.net >> >> For policy questions, send mail to: >> Richard Nute: ri...@ieee.org >> Jim Bacher: j.bac...@ieee.org >> >> All emc-pstc postings are archived and searchable on the web at: >> No longer online until our new server is brought online and the old >> messages are imported into the new server. >> > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Michael Garretson:pstc_ad...@garretson.org > Dave Healddavehe...@mediaone.net > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > No longer online until our new server is brought online and the old > messages are imported into the new server. > --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on t
Re: High Frequency Pre-amp
I don't understand the distinction being made here. I understand that a sensitive preamplifier is more easily saturated than one with lower gain or noise figure, but I don't understand why other things equal a Mini-Circuit preamp would be more prone to saturation than a MITEQ. Please explain. -- >From: "Brent DeWitt" >To: "Robert Macy" , "Ken Javor" , , >Subject: RE: High Frequency Pre-amp >Date: Fri, Dec 21, 2001, 8:34 PM > > Robert brings up a very good point. It is the main difference between a $4 > ERA monolithic amp from MiniCircuits and a packaged $1200 Miteq amp. While > saying that, I think MiniCircuits is a great company with a range of > products that are well characterized and worth every penny. > > Regards, > > Brent DeWitt > > -Original Message- > From: owner-emc-p...@majordomo.ieee.org > [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Robert Macy > Sent: Friday, December 21, 2001 1:09 PM > To: Ken Javor; rehel...@mmm.com; emc-p...@majordomo.ieee.org > Subject: Re: High Frequency Pre-amp > > > > Just a reminderalways make certain that no signal gets in to "saturate", > or even start to overdrive, your amplifier at frequencies you're not looking > at. > > - Robert - > >Robert A. Macy, PEm...@california.com >408 286 3985 fx 408 297 9121 >AJM International Electronics Consultants >619 North First St, San Jose, CA 95112 > > > -Original Message- > From: Ken Javor > To: rehel...@mmm.com ; emc-p...@majordomo.ieee.org > > Date: Friday, December 21, 2001 11:42 AM > Subject: Re: High Frequency Pre-amp > > >> >>MITEQ and Mini-Circuits come to mind for octave and multi-octave band > amps. >>HP (Agilent) makes the the 8348A covering 1 - 26.5 GHz around $14 K. The > HP >>model has a 10 dB noise figure and 25 dB gain below 20 GHz. With MITEQ you >>can pick your noise figure and gain from a large variety of models. >>Mini-Circuits is the low price leader, I saw amps up to 8 GHz but you would >>need several models and the price will still likely be less than with the >>others. If you are using an HP8566 or similar model which uses harmonic >>mixing above 2 GHz then you need enough gain to push the signal above the >>degraded noise floor. >> >>-- >>>From: rehel...@mmm.com >>>To: emc-p...@majordomo.ieee.org >>>Subject: High Frequency Pre-amp >>>Date: Fri, Dec 21, 2001, 10:16 AM >>> >> >>> >>> This question may have recently posted but I'm not able to search the >>> archives so I'll >>> ask again. >>> >>> We have an immediate need for a pre-amp above 1000 MHz. Would you be so >>> kind >>> as to let me know what brands/models and frequency range you are using. > Any >>> pro/con >>> insights would be welcome as well. Please contact me on or off-line. >>> >>> Thanks, >>> Bob Heller >>> 3M Product Safety, 76-1-01 >>> St. Paul, MN 55107-1208 >>> Tel: 651- 778-6336 >>> Fax: 651-778-6252 >>> >>> >>> --- >>> This message is from the IEEE EMC Society Product Safety >>> Technical Committee emc-pstc discussion list. >>> >>> Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ >>> >>> To cancel your subscription, send mail to: >>> majord...@ieee.org >>> with the single line: >>> unsubscribe emc-pstc >>> >>> For help, send mail to the list administrators: >>> Michael Garretson:pstc_ad...@garretson.org >>> Dave Healddavehe...@mediaone.net >>> >>> For policy questions, send mail to: >>> Richard Nute: ri...@ieee.org >>> Jim Bacher: j.bac...@ieee.org >>> >>> All emc-pstc postings are archived and searchable on the web at: >>> No longer online until our new server is brought online and the old >>> messages are imported into the new server. >>> >> > > > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Michael Garretson:pstc_ad...@garretson.org > Dave Healddavehe...@mediaone.net > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > No longer online until our new server is brought online and the old > messages are imported into the new server. > --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single l
Re: noise figure
Take the limit you are measuring to, and subtract the transducer factor and any cable losses. That yields the receiver signal in dBuV which corresponds to a spec level signal. Subtract off a factor for how much you want the receiver noise floor to be below the spec level, typically 6 dB. Call this level N. Then basic statistical thermodynamic theory says that N = kTBF, where K is Boltzman's constant (the ideal gas law constant divided by Avogadro's number), T is absolute temperature in Kelvin, B is bandwidth in Hertz, and F is the noise figure. At room temperature, 25 degrees Celsius or 298 Kelvin, N = -67 dBuV/Hz, with the bandwidth dependency going as 10 log (BW) because the basic equation is for noise power. Now given your bandwidth, say 120 kHz, you can solve for the necessary noise figure. If your receiver/analyzer noise figure is higher than that needed, there is another simple equation that will allow you to specify a preamp that will allow the combination measurement system to perform as required. -- >From: "KC CHAN [PDD]" >To: >Subject: noise figure >Date: Fri, Dec 21, 2001, 6:42 PM > > > Hi all > > It may not be purely EMC question, actually it is RF related, but I am sure > the experts here can answer my questions. > > We all know that we need to have a pre-amp. that is as lower noise figure > as possible, but how low it is enough or how it is related to the noise > floor viewed by a receiver or spectrum analyzer. > > Thank you > KC Chan > > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Michael Garretson:pstc_ad...@garretson.org > Dave Healddavehe...@mediaone.net > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > No longer online until our new server is brought online and the old > messages are imported into the new server. > --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: surges on 24VAC
At 15:16 21/12/01 -0500, John Juhasz wrote: > >If the 24V AC is generated via a Class II Direct Plug-In power >pack, wouldn't the test be run 'through' the power pack - the power >pack plugged into the outlet on the surge tester? I see your point, but as I understand it, only if the power pack is made available with the apparatus to the end user, i.e. a system. This is up to the manufacturer to define. Enci --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: surges on 24VAC
I read in !emc-pstc that John Juhasz wrote (in <2a1845f4cde8d511b4400090279c703b14e...@bctexc10.na.ilxi.net>) about 'surges on 24VAC', on Fri, 21 Dec 2001: >The functional circuit operates off of 24V AC, >but the primary power is AC Mains - whether it's >supplied through a line cord/power entry module combo >or a direct plug-in transformer. We aren't told what supplies the 24 V a.c. . It may be a supply that is highly unlikely to experience a surge of any sort. Whatever the supply system is, the surge test intended for mains voltage ports is not appropriate to be applied to the 24 V a.c. port. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: New China Compulsory Certification
As officially announced on December 7th, 2001, CCC mark will take effective from May 1st 2002, replacing current CCIB (Safety) mark and CCEE (Great Wall) mark. I am currently in touch with relevant Chinese authorities for details. Leslie cecil.gitt...@kodak.com wrote: From: Cecil A. Gittens Does anyone have information about products that will required EMC certification to meet the new China Compulsory Certification system. It was mentioned that they will host meetings in the future to introduce this new system. Regards Cecil --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. - Do You Yahoo!? Send your FREE holiday greetings online at Yahoo! Greetings.
RE: High Frequency Pre-amp
Robert brings up a very good point. It is the main difference between a $4 ERA monolithic amp from MiniCircuits and a packaged $1200 Miteq amp. While saying that, I think MiniCircuits is a great company with a range of products that are well characterized and worth every penny. Regards, Brent DeWitt -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Robert Macy Sent: Friday, December 21, 2001 1:09 PM To: Ken Javor; rehel...@mmm.com; emc-p...@majordomo.ieee.org Subject: Re: High Frequency Pre-amp Just a reminderalways make certain that no signal gets in to "saturate", or even start to overdrive, your amplifier at frequencies you're not looking at. - Robert - Robert A. Macy, PEm...@california.com 408 286 3985 fx 408 297 9121 AJM International Electronics Consultants 619 North First St, San Jose, CA 95112 -Original Message- From: Ken Javor To: rehel...@mmm.com ; emc-p...@majordomo.ieee.org List-Post: emc-pstc@listserv.ieee.org Date: Friday, December 21, 2001 11:42 AM Subject: Re: High Frequency Pre-amp > >MITEQ and Mini-Circuits come to mind for octave and multi-octave band amps. >HP (Agilent) makes the the 8348A covering 1 - 26.5 GHz around $14 K. The HP >model has a 10 dB noise figure and 25 dB gain below 20 GHz. With MITEQ you >can pick your noise figure and gain from a large variety of models. >Mini-Circuits is the low price leader, I saw amps up to 8 GHz but you would >need several models and the price will still likely be less than with the >others. If you are using an HP8566 or similar model which uses harmonic >mixing above 2 GHz then you need enough gain to push the signal above the >degraded noise floor. > >-- >>From: rehel...@mmm.com >>To: emc-p...@majordomo.ieee.org >>Subject: High Frequency Pre-amp >>Date: Fri, Dec 21, 2001, 10:16 AM >> > >> >> This question may have recently posted but I'm not able to search the >> archives so I'll >> ask again. >> >> We have an immediate need for a pre-amp above 1000 MHz. Would you be so >> kind >> as to let me know what brands/models and frequency range you are using. Any >> pro/con >> insights would be welcome as well. Please contact me on or off-line. >> >> Thanks, >> Bob Heller >> 3M Product Safety, 76-1-01 >> St. Paul, MN 55107-1208 >> Tel: 651- 778-6336 >> Fax: 651-778-6252 >> >> >> --- >> This message is from the IEEE EMC Society Product Safety >> Technical Committee emc-pstc discussion list. >> >> Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ >> >> To cancel your subscription, send mail to: >> majord...@ieee.org >> with the single line: >> unsubscribe emc-pstc >> >> For help, send mail to the list administrators: >> Michael Garretson:pstc_ad...@garretson.org >> Dave Healddavehe...@mediaone.net >> >> For policy questions, send mail to: >> Richard Nute: ri...@ieee.org >> Jim Bacher: j.bac...@ieee.org >> >> All emc-pstc postings are archived and searchable on the web at: >> No longer online until our new server is brought online and the old >> messages are imported into the new server. >> > --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
noise figure
Hi all It may not be purely EMC question, actually it is RF related, but I am sure the experts here can answer my questions. We all know that we need to have a pre-amp. that is as lower noise figure as possible, but how low it is enough or how it is related to the noise floor viewed by a receiver or spectrum analyzer. Thank you KC Chan --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.