Re: Plug-In Power Supplies
Peter, I have some documents on these but they are in hard copy format. Give me your fax/phone number and I will get them to you. Thanks Homi Ahmadi Cortech Systems Tel: 805-582-4400 EXT 214 E-mail: hahm...@cortechsys.com pe...@itl.co.il (Peter Merguerian) on 10/14/98 02:16:40 PM Please respond to pe...@itl.co.il (Peter Merguerian) To: 'emc-pstc list server' Emc-Pstc emc-p...@majordomo.ieee.org cc: (bcc: Homi Ahmadi/CORTECH) Subject: Plug-In Power Supplies Dear Members Can anyone help in some guidelines for the manufacture of a Class II plug-in power supply for use with cellular telephone equipment? I am interested in the plug dimensions for North America (polarized 125 V parallel blade plug configuration), and for Europe (230 V euro plug which will fit most countries' sockets except the UK). The unit will be designed with interchangeable bases which will accomodate the above specified plug configurations. I am interested in specs and standards for the plugs and the base material. UL1950 and EN 60 950 do not address this type of construction but I know that some of you can help out. Thanks and Best Regards, - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Yellow Zinc
Hi Guys, Does anyone know what a typical conductivity or resistivity is for yellow zinc coating??? Jim Dr. Jim Knightene-mail: jim.knigh...@sandiegoca.ncr.com Senior Consulting Engineer NCR 17095 Via del Campo San Diego, CA 92127 http://www.ncr.com Tel: 619-485-2537 Fax: 619-485-3788 - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Conductivity Question
Are we talking ohms or ohms per square? If it's ohms per square, .3 or .4 seems a little high for a metal sheet. Depending upon alot of factors, I'm used to Cu conductive coating on plastic running roughly just a little less than this and Ni conductive coating on plastic running just under an ohm. Doug On Wed, 14 Oct 1998 b...@namg.us.anritsu.com wrote: Hi Nancy, The following is my two cents worth. Please correct me. I have done a ohms test on the two materials. Both testing at .3 to .4 ohms. My customer has already gone through their EMI Testing... It seems to me that only data of .3 and .4 ohms is not enough. We still don't know the thickness of the coating, and also the data is only DC value instead of RF value. Do you know how much margins of the EMI test your customer has got with the original case? Even though we know all necessary data, it's still very hard to say what role the conductivity plays in the final EMI profile of the EUT, which depends on too many parameters. We have to do some test. If your customer was reluctant to redo the EMI test, can you suggest a Shielding Effectiveness (SE) comparison test? The test needs only two empty cases with a comb generator inside. The SE test results are straightforward to convince your customer. Best Regards, Barry Ma - Original Text From: ed.pr...@cubic.com, on 10/14/98 1:17 PM: Hello Group! The following is a non-member post which was submitted to the admins, but which really ought to be posted. (If you post a reply, remember to copy Ludvigsen, but not me.) From: Nancy Ludvigsen nludvig...@emtengineering.com Subject: Conductivity Question Date: Wed, 14 Oct 1998 15:53:56 -0500 To: 'ed.pr...@cubic.com' ed.pr...@cubic.com, 'j...@gwmail.monarch.com' j...@gwmail.monarch.com Hi Guys: I am a manufacturers rep. for a sheet metal fabricator. I have a customer that is currently manufacturing an enclosure our or Galvannel. This unit is welded and they are not currently painting over the welded areas. This will cause corrosion over time. I am suggesting that they go to a zinc plated cold rolled steel for a better finish, and also our buying power is suited for steel. My customer has already gone through their EMI Testing and is hesitant to change to zinc plated cold rolled steel because they do not know the difference in conductivity between the two materials. I have done a ohms test on the two materials. Both testing at .3 to .4 ohms. Can you direct me to a source to get more information on the conductivity of the two metal finishes? Or give me more direction as to how to address this issue? Any information is greatly appreciated. Thank you in advance. Nancy -- Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA. USA 619-505-2780 Date: 10/14/1998 Time: 12:17:52 -- - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Plug-In Power Supplies
Homi Hi! I geatly appreciate your help. My fax # is 972-3-5339019. My phone # is 972-3-5339022. Please do not hesitate to call when you need something. Regards, Peter From: hahm...@cortechsys.com To: pe...@itl.co.il (Peter Merguerian) Copies to: 'emc-pstc list server' Emc-Pstc emc-p...@majordomo.ieee.org Date sent: Wed, 14 Oct 1998 17:04:14 -0700 Subject:Re: Plug-In Power Supplies Peter, I have some documents on these but they are in hard copy format. Give me your fax/phone number and I will get them to you. Thanks Homi Ahmadi Cortech Systems Tel: 805-582-4400 EXT 214 E-mail: hahm...@cortechsys.com pe...@itl.co.il (Peter Merguerian) on 10/14/98 02:16:40 PM Please respond to pe...@itl.co.il (Peter Merguerian) To: 'emc-pstc list server' Emc-Pstc emc-p...@majordomo.ieee.org cc: (bcc: Homi Ahmadi/CORTECH) Subject: Plug-In Power Supplies Dear Members Can anyone help in some guidelines for the manufacture of a Class II plug-in power supply for use with cellular telephone equipment? I am interested in the plug dimensions for North America (polarized 125 V parallel blade plug configuration), and for Europe (230 V euro plug which will fit most countries' sockets except the UK). The unit will be designed with interchangeable bases which will accomodate the above specified plug configurations. I am interested in specs and standards for the plugs and the base material. UL1950 and EN 60 950 do not address this type of construction but I know that some of you can help out. Thanks and Best Regards, - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Harmonics Class A vs. Class D
Hellow HP and Group: I am a manufacturers rep. for a Laser Beam Printer. I have a buyer who demand coply with EN 61000-3-2 for our product. But I confuse definition of 'P' in EN 61000-3-2 as follow... -- 5.Classification of equipment Class A : ...
RE: Yellow Zinc
Don't have the figures to hand but having checked it out a while ago we have moved from the gold/yellow zinc passivation on steel parts to the silver/clear finish: UK spec: BRIGHT ZINC PLATE TO BS 1706 Fe/Zn 8 c 1A US spec: BRIGHT ZINC, ASTM B633, TYPE III, Fe/Zn 8 This has a much lower resistance. We found the gold unacceptable for emc considerations. Chris James Engineering Services Manager Dolby Labs Inc. -Original Message- From: Knighten, Jim [mailto:knigh...@exchange.sandiegoca.ncr.com] Sent: Thursday, October 15, 1998 1:20 AM To: 'emc-pstc list server' Subject: Yellow Zinc Hi Guys, Does anyone know what a typical conductivity or resistivity is for yellow zinc coating??? Jim Dr. Jim Knightene-mail: jim.knigh...@sandiegoca.ncr.com Senior Consulting Engineer NCR 17095 Via del Campo San Diego, CA 92127 http://www.ncr.com Tel: 619-485-2537 Fax: 619-485-3788 - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Test procedure for C-Tick
Hello group, which supply voltage is used according to the C-Tick regulations? We are selling information technology equipment in Europe and to the United States. Because of the FCC regulations some tests are done at 110V. Is there any regulation regarding to the amount of Volt in Australia? Does the C-Tick also accept test assemblies with 110 V? Iris Iris Scheyer Quality Assurance Engineering ELSA AG Sonnenweg 11 Phone:+49-(0)241-606-0 52070 Aachen Fax: +49-(0)241-606-2099 Germany Email:ische...@elsa.de - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
RE: Yellow Zinc
I will second what Chris says. The yellow zinc has a surface resistance that must be penetrated in order to have conduction across joints. Jim Allan Racal-Datacom -Original Message- From: James, Chris [SMTP:c...@dolby.co.uk] Sent: Thursday, October 15, 1998 5:49 AM To: 'Knighten, Jim'; 'emc-pstc list server' Subject:RE: Yellow Zinc Don't have the figures to hand but having checked it out a while ago we have moved from the gold/yellow zinc passivation on steel parts to the silver/clear finish: UK spec: BRIGHT ZINC PLATE TO BS 1706 Fe/Zn 8 c 1A US spec: BRIGHT ZINC, ASTM B633, TYPE III, Fe/Zn 8 This has a much lower resistance. We found the gold unacceptable for emc considerations. Chris James Engineering Services Manager Dolby Labs Inc. -Original Message- From: Knighten, Jim [mailto:knigh...@exchange.sandiegoca.ncr.com] Sent: Thursday, October 15, 1998 1:20 AM To: 'emc-pstc list server' Subject: Yellow Zinc Hi Guys, Does anyone know what a typical conductivity or resistivity is for yellow zinc coating??? Jim Dr. Jim Knightene-mail: jim.knigh...@sandiegoca.ncr.com Senior Consulting Engineer NCR 17095 Via del Campo San Diego, CA 92127 http://www.ncr.com Tel: 619-485-2537 Fax: 619-485-3788 - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: IEEE/ EMC Society Meeting
Passing on another non-member post.. Jim Hight, Kevin kev...@exabyte.com 10/14 7:16 PM IEEE EMC SOCIETY ROCKY MOUNTAIN CHAPTER OCTOBER MEETING TUESDAY OCTOBER 20, 1998 Mr. Robert W. Dockey Hewlett-Packard Company New Techniques for Reducing Printed Circuit Board Common-Mode Radiation WHERE:NIST - Boulder 325 Broadway Boulder, Colorado 80303 TIME: 7:00 p.m. DIRECTIONS: From Denver take I-25 to Highway 36. Go NW on Highway 36 to Boulder. Continue on Highway 36 to Baseline Road. Take Baseline Road West one block to 27th Way. Turn South (left) on 27th Way and continue past Broadway into the NIST parking lot. Enter through the Main doors (facing Broadway) and check in with the guard at the front desk, the guard will direct you to our meeting room. DINNER: 5:30 p.m. - 6:45 p.m. Rafferty's Restaurant 2805 Pearl, Boulder, Colorado 80301, Phone; (303) 447-2665 Rafferty's is on the corner of 28th (Highway 36) and Pearl. From Baseline road, continue North on Highway 36 (28th Street) 5 stop lights. Take next Right into the parking lot of Rafferty's. See you there! RSVP to Kevin Hight at 303-417-5534 by noon on the 19th. For more information please contact one of the IEEE Rocky Mountain Chapter EMC Society Officers listed below. Chairman: Jeff Doolittle 303-449-4165 Vice Chairman:Joe Kramer 303-449-4165 Secretary:Kevin Hight 303-417-5534 Treasurer:Wes Smith 970-962-7472 EVERYONE IS WELCOME ! AUTHOR BIOGRAPHY Robert Dockey Bob is the EMC Engineering Group manager at the Hewlett Packard division in Vancouver Washington. He has a BSEE from the University of Missouri at Rolla and is certified as an EMC engineer by the National Association of Radio and Television Engineers. He is the author of three technical papers on various EMC subjects and is a member and Distinguished Lecturer of the IEEE EMC Society. Bob has been with Hewlett Packard for 13 years as both an EMC engineer and engineering manager. Previously, he spent 13 years as a TEMPEST engineering manager for TRW in Colorado Springs, Colo. INTRODUCTION Have you ever had the experience of believing that you had done everything humanly possible to reduce the radiated emissions from an unshielded printed circuit assembly and yet still measure unacceptable margins? If so, this presentation could help explain the reasons why. Even when all of the common emission suppression measures like power supply decoupling, cable filtering, loop area control and full ground planes have been utilized, there is still one dominant coupling mechanism remaining which can be manipulated to improve the margin. Unfortunately it may also set a lower limit on the possible emission level which can be obtained from a specific design. This mechanism is referred to as Ground Plane Voltage Gradient contamination. This presentation will attempt to describe and analyze this radiated emission mechanism and present several design techniques which can be used to deal with it successfully. New Techniques for Reducing Printed Circuit Board Common-Mode Radiation ABSTRACT A multi-layer printed circuit board with a good ground plane can produce common-mode radiation similar to a dipole antenna. This ground plane is commonly thought of as a low impedance path for returning currents and one which is of constant potential across its area. In fact, these currents give rise to voltage gradients in the plane which act as sources of common-mode current. The majority of the RF current flowing along a signal trace on a multi-layer printed circuit board (PCB) returns on the ground plane directly beneath the signal trace. However, a small portion of the ground-plane current also can return via indirect paths causing the PCB and attached cables (if present) to produce common-mode radiation similar to a dipole antenna. Several new techniques to reduce these emissions by lowering the inductance of the ground return or by bypassing the common-mode current on the cables are presented. These cost-effective techniques can be employed on two-sided or multi-layer PCBs. Previous independent work by German, Ott and Paul experimentally investigated the radiated emissions from a printed circuit board (PCB) with a digital circuit that produced current on a signal trace that returned via an adjacent ground-return trace. They demonstrated that if this two-wire transmission-line is slightly unbalanced, it will radiate as an asymmetric dipole antenna producing common-mode radiation at much greater levels than the differential-mode radiation from the current loop. A direct prediction of this radiation was later performed by Hardin, Paul and Naishadham. In 1993, Dockey discovered that a relatively small PCB with a solid ground-plane could also produce common-mode radiation. On this
RE: Test procedure for C-Tick
You have to look to the standards for the answer. Since the Australian standards follow CISPR, the standards require that you test at the nominal voltage and frequency of the country. Australia's power system is 240V 50 Hz (some areas in the outback can reach as high as 250V nominal). A retest of the radiated emissions would most likely show no major differences; however, you may see significant differences in the conducted emissions at the lower frequencies. -- From: ische...@elsa.de [SMTP:ische...@elsa.de] Sent: Thursday, October 15, 1998 6:56 AM To: emc-p...@majordomo.ieee.org Subject: Test procedure for C-Tick Hello group, which supply voltage is used according to the C-Tick regulations? We are selling information technology equipment in Europe and to the United States. Because of the FCC regulations some tests are done at 110V. Is there any regulation regarding to the amount of Volt in Australia? Does the C-Tick also accept test assemblies with 110 V? Iris Iris Scheyer Quality Assurance Engineering ELSA AG Sonnenweg 11 Phone:+49-(0)241-606-0 52070 Aachen Fax: +49-(0)241-606-2099 Germany Email:ische...@elsa.de - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re[2]: Yellow Zinc
I will also second that. We have turned away from using yellow zinc coating, as well. We found that the yellow zinc coating was prone to early oxidation which had a purple color. This oxidation was evident on most surfaces, but was most prevalent at the joining surfaces (Murphy's Law). In fact if we needed to, we could always find out who handled these parts by the oxidized fingerprints. Clear/bright zinc was found to be more preferable than yellow zinc in this regard. And as far as conductivity goes, the clear/bright zinc coating has much lower readings. If memory serves me right from tests from a past employer: Yellow zinc measured about 0.5 - 4.5 ohms/square Clear/Bright zinc measured about 0.2 - 0.5 ohms/square As for joining parts together, mating parts with yellow zinc coating were sometimes difficult get a good low-impedance connection. We have never had such a problem with the clear.bright zinc coating. The large yellow results were attributed to points of oxidation as the test probes did not pentrate the surface. Just some past experiences to share. Best regards, Ron Pickard ron_pick...@hypercom.com __ Reply Separator _ Subject: RE: Yellow Zinc Author: Allan James james_al...@racal.com at INTERNET List-Post: emc-pstc@listserv.ieee.org Date:10/15/98 8:20 AM I will second what Chris says. The yellow zinc has a surface resistance that must be penetrated in order to have conduction across joints. Jim Allan Racal-Datacom -Original Message- From: James, Chris [SMTP:c...@dolby.co.uk] Sent: Thursday, October 15, 1998 5:49 AM To: 'Knighten, Jim'; 'emc-pstc list server' Subject:RE: Yellow Zinc Don't have the figures to hand but having checked it out a while ago we have moved from the gold/yellow zinc passivation on steel parts to the silver/clear finish: UK spec: BRIGHT ZINC PLATE TO BS 1706 Fe/Zn 8 c 1A US spec: BRIGHT ZINC, ASTM B633, TYPE III, Fe/Zn 8 This has a much lower resistance. We found the gold unacceptable for emc considerations. Chris James Engineering Services Manager Dolby Labs Inc. -Original Message- From: Knighten, Jim [mailto:knigh...@exchange.sandiegoca.ncr.com] Sent: Thursday, October 15, 1998 1:20 AM To: 'emc-pstc list server' Subject: Yellow Zinc Hi Guys, Does anyone know what a typical conductivity or resistivity is for yellow zinc coating??? Jim Dr. Jim Knightene-mail: jim.knigh...@sandiegoca.ncr.com Senior Consulting Engineer NCR 17095 Via del Campo San Diego, CA 92127 http://www.ncr.com Tel: 619-485-2537 Fax: 619-485-3788 - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Conductivity Question
Hi Doug, You are right. Thanks for the correction. The unit to describe the surface conductivity should be ohm per square. Actually, I use Conductivity Prob, purchased from SPRAYLAT, to check surface conductivity. --Barry. - Original Text From: Douglas L McKean dmck...@corp.auspex.com, on 10/14/98 8:48 PM: Are we talking ohms or ohms per square? If it's ohms per square, .3 or .4 seems a little high for a metal sheet. Depending upon alot of factors, I'm used to Cu conductive coating on plastic running roughly just a little less than this and Ni conductive coating on plastic running just under an ohm. Doug On Wed, 14 Oct 1998 b...@namg.us.anritsu.com wrote: Hi Nancy, The following is my two cents worth. Please correct me. I have done a ohms test on the two materials. Both testing at .3 to .4 ohms. My customer has already gone through their EMI Testing... It seems to me that only data of .3 and .4 ohms is not enough. We still don't know the thickness of the coating, and also the data is only DC value instead of RF value. Do you know how much margins of the EMI test your customer has got with the original case? Even though we know all necessary data, it's still very hard to say what role the conductivity plays in the final EMI profile of the EUT, which depends on too many parameters. We have to do some test. If your customer was reluctant to redo the EMI test, can you suggest a Shielding Effectiveness (SE) comparison test? The test needs only two empty cases with a comb generator inside. The SE test results are straightforward to convince your customer. Best Regards, Barry Ma - Original Text From: ed.pr...@cubic.com, on 10/14/98 1:17 PM: Hello Group! The following is a non-member post which was submitted to the admins, but which really ought to be posted. (If you post a reply, remember to copy Ludvigsen, but not me.) From: Nancy Ludvigsen nludvig...@emtengineering.com Subject: Conductivity Question Date: Wed, 14 Oct 1998 15:53:56 -0500 To: 'ed.pr...@cubic.com' ed.pr...@cubic.com, 'j...@gwmail.monarch.com' j...@gwmail.monarch.com Hi Guys: I am a manufacturers rep. for a sheet metal fabricator. I have a customer that is currently manufacturing an enclosure our or Galvannel. This unit is welded and they are not currently painting over the welded areas. This will cause corrosion over time. I am suggesting that they go to a zinc plated cold rolled steel for a better finish, and also our buying power is suited for steel. My customer has already gone through their EMI Testing and is hesitant to change to zinc plated cold rolled steel because they do not know the difference in conductivity between the two materials. I have done a ohms test on the two materials. Both testing at .3 to .4 ohms. Can you direct me to a source to get more information on the conductivity of the two metal finishes? Or give me more direction as to how to address this issue? Any information is greatly appreciated. Thank you in advance. Nancy -- Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA. USA 619-505-2780 Date: 10/14/1998 Time: 12:17:52 -- - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
RE: Yellow Zinc
Sometimes this gets confused with yellow-chromate and is usually anodized onto the metal. Its great for incoming inspection because they can see it clearly, but not so great for conductivity. The bright zinc seems to satisfy everybody, they can inspect it and we seem to be getting good conductivity from it. Gary McInturff -Original Message- From: Allan, James [SMTP:james_al...@racal.com] Sent: Thursday, October 15, 1998 5:20 AM To: 'emc-p...@ieee.org' Subject:RE: Yellow Zinc I will second what Chris says. The yellow zinc has a surface resistance that must be penetrated in order to have conduction across joints. Jim Allan Racal-Datacom -Original Message- From: James, Chris [SMTP:c...@dolby.co.uk] Sent: Thursday, October 15, 1998 5:49 AM To: 'Knighten, Jim'; 'emc-pstc list server' Subject:RE: Yellow Zinc Don't have the figures to hand but having checked it out a while ago we have moved from the gold/yellow zinc passivation on steel parts to the silver/clear finish: UK spec: BRIGHT ZINC PLATE TO BS 1706 Fe/Zn 8 c 1A US spec: BRIGHT ZINC, ASTM B633, TYPE III, Fe/Zn 8 This has a much lower resistance. We found the gold unacceptable for emc considerations. Chris James Engineering Services Manager Dolby Labs Inc. -Original Message- From: Knighten, Jim [mailto:knigh...@exchange.sandiegoca.ncr.com] Sent: Thursday, October 15, 1998 1:20 AM To: 'emc-pstc list server' Subject: Yellow Zinc Hi Guys, Does anyone know what a typical conductivity or resistivity is for yellow zinc coating??? Jim Dr. Jim Knightene-mail: jim.knigh...@sandiegoca.ncr.com Senior Consulting Engineer NCR 17095 Via del Campo San Diego, CA 92127 http://www.ncr.com Tel: 619-485-2537 Fax: 619-485-3788 - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
NPSS's 4th Annual Vendors' Night - Info
The NORTHEAST PRODUCT SAFETY SOCIETY, Inc. presents the 4th Annual Vendors' Night November 18, 1998 FREE Admission!! -- Deli-Deluxe Buffet, Coffee and Dessert, 6-7:30pm. FREE to NPSS Members, Others; US$10.00 in advance, $15.00 the nite of the event. (Details Below) LOCATION: Boxborough Woods (Holiday Inn), One Adams Pl. Boxborough MA - Visit with the Agencies, Test Labs, Consultants Suppliers of components, materials and test equipment. Last year's exhibitors included; Associated Research, BSI Testing, CSA, Chomerics Test Services, Compliance Engineering, Compliance Plus, Conti-Younger/Corcom, Curtis-Straus, Detecon, DEC, Educated Design Dev't, Entela, EuroPort/EUROCONSULT, FM, Haefely Trench, Integrity Design Test, Int'l Product Safety News, Intertek Testing Services, M. Swank As- sociates, Marathon Sales, MET Laboratories, National Technical Systems, Olsen Technical Sales, Panel Components Corp, Pat Associates, QuadTech, Quantum Change EMC Systems, Retlif Testing Labs, San-O Industrial Corp., Scientific Devices, Stratus Test Labs, Teeco, TuV Essen, TuV Product Service, TuV Rheinland of NA, UL, Voltech Instruments, WW Wilson Associates's and more ___ Meet and network with your friends, colleagues, and vendors. 5:00 P.M. Registration Cash Bar Opens, Free Appetizers(Courtesy-Entela) 5:30 Exhibition Hall Opens 6:00-7:30 Deli-Deluxe Buffet: (Details Below) 7:30 Short Program and Announcements 9:00 Exhibition Hall Closes Additional Info on NPSS's Website: http://www.safetylink.com/#NPSS * For Deli-Deluxe Buffet reservations; Contact: Bill Graham, Scientific Devices New England Ph(978) 568-3366 Fx(978) 568-1454 Email billg_s...@compuserve.com A reservation form (text-based) can be found at: www.safetylink.com/npssbuff.txt An online form can be found at: www.safetylink.com/npssbuff.htm Vendors: Contact Art Michael Phone: (860) 344-1651 Fax (860) 346-9066 Email:n...@safetylink.com ### REF:vniteinf.txt (9/98c) - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Please psot position on your website
Hi again, groupies! Here's a non-member submission of and EMC job position for Cisco in San Jose, CA, USA. From: Audra Bauer auba...@cisco.com Subject: Please psot position on your website Date: Wed, 14 Oct 1998 19:07:16 -0700 To: emc-p...@ieee.org Cc: auba...@cisco.com, staw...@cisco.com Dear Webmaster, Please post this job listing on your web site. If you have any questions, please contact me. Thank you. Audra Bauer Job Title: EMC Design Engineer Company: Cisco Systems Location: San Jose, CA Provide technical expertise and leadership in the area of EMC conceptual design, and test. Duties include provide EMC design advice to electrical and mechanical engineers, CAD designers, and work with signal integrity engineers at PCB level. Provide technical support to EMC test engineers, and work on board and system level issues. Perform EMC design and analysis of electronic circuits and systems. Qualifications: Minimum BSEE, MSEE preferred. EMC design and test experience. Interested persons should email their resumes to Stan Wong Email: staw...@cisco.com Phone: 408 527-6288 //////// Audra L. Bauer Employment Coordinator Enterprise Line of Business Cisco Systems (408) 527-6566 or (800) 326-1941 x76566 ////// ---End of Original Message- -- Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA. USA 619-505-2780 List-Post: emc-pstc@listserv.ieee.org Date: 10/15/1998 Time: 09:27:03 -- - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Conductivity Question
Nancy: I'm not familiar with the Galvanel surface treatment, but if it is some type of zinc coating on the steel, welding is a bad technique. I understand that the heat of welding vaporizes the zinc, resulting in hazardous vapors in the work area. Secondly, the zinc tends to contaminate the fused metal, making for a lower quality joint. Next, I think the surface coating on the base steel is generally irrelevant to the shielding performance. The surface treatment (my favorite is electro tin and fuse) can maintain conductivity, but any mild steel barrier that can support itself will have almost unmeasurably high SE. Aside from the cosmetic aspects, a 60 mil thick sheet of steel, with a 2 mil thick layer of rust on each side, will still be an excellent shield. As long as the joints are welded, you could just let it rust. Or spray paint it, or even bond on a fluidized bed epoxy layer. Regards, Ed Subject: Re: Conductivity Question Date: Wed, 14 Oct 1998 12:17:50 -0800 To: EMC-PSTC emc-p...@majordomo.ieee.org, Nancy Ludvigsen nludvig...@emtengineering.com Hello Group! The following is a non-member post which was submitted to the admins, but which really ought to be posted. (If you post a reply, remember to copy Ludvigsen, but not me.) From: Nancy Ludvigsen nludvig...@emtengineering.com Subject: Conductivity Question Date: Wed, 14 Oct 1998 15:53:56 -0500 To: 'ed.pr...@cubic.com' ed.pr...@cubic.com, 'j...@gwmail.monarch.com' j...@gwmail.monarch.com Hi Guys: I am a manufacturers rep. for a sheet metal fabricator. I have a customer that is currently manufacturing an enclosure our or Galvannel. This unit is welded and they are not currently painting over the welded areas. This will cause corrosion over time. I am suggesting that they go to a zinc plated cold rolled steel for a better finish, and also our buying power is suited for steel. My customer has already gone through their EMI Testing and is hesitant to change to zinc plated cold rolled steel because they do not know the difference in conductivity between the two materials. I have done a ohms test on the two materials. Both testing at .3 to .4 ohms. Can you direct me to a source to get more information on the conductivity of the two metal finishes? Or give me more direction as to how to address this issue? Any information is greatly appreciated. Thank you in advance. Nancy -- Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA. USA 619-505-2780 List-Post: emc-pstc@listserv.ieee.org Date: 10/15/1998 Time: 09:56:38 -- - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Job Opportunity at Cisco Systems
Another job posting for Cisco (in California, USA?): From: Audra Bauer auba...@cisco.com Subject: Job Opportunity at Cisco Systems Date: Thu, 15 Oct 1998 13:05:09 -0700 To: emc-p...@ieee.org Cc: auba...@cisco.com, staw...@cisco.com, sgroz...@cisco.com Dear Webmaster, Please post this job opportunity on your website. The recruiter for this position is Stan Wong. Thank you. Audra Bauer PTT/Telecommunication Design/Test Engineer MSEE or equivalent and three or more years experiences in telecom compliance testing environment or hardware design. Strong test or design engineering background with ISDN-BRI/PRI, E1/E3, T1/T3, ATM SONET/SDH OC3, OC12 and other interfaces. Hand on experiences with telecom conformance test equipment, ability to learn quickly, and good communication skills. This engineer will be responsible for working with design engineers on new product development, consult DE on new standard requirements, testing prototypes, certifying products based on ITU-T, CTR's and other international telecom test standards, preparing test documentations, and assisting in country certification. Some international travel required. Please email resumes to: Recruiter:Stan Wong Phone:408-527-6566 Email:staw...@cisco.com //////// Audra L. Bauer Employment Coordinator Enterprise Line of Business Cisco Systems (408) 527-6566 or (800) 326-1941 x76566 ////// //////// Audra L. Bauer Employment Coordinator Enterprise Line of Business Cisco Systems (408) 527-6566 or (800) 326-1941 x76566 ////// //////// Audra L. Bauer Employment Coordinator Enterprise Line of Business Cisco Systems (408) 527-6566 or (800) 326-1941 x76566 ////// //////// Audra L. Bauer Employment Coordinator Enterprise Line of Business Cisco Systems (408) 527-6566 or (800) 326-1941 x76566 ////// //////// Audra L. Bauer Employment Coordinator Enterprise Line of Business Cisco Systems (408) 527-6566 or (800) 326-1941 x76566 ////// ---End of Original Message- -- Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA. USA 619-505-2780 List-Post: emc-pstc@listserv.ieee.org Date: 10/15/1998 Time: 13:50:59 -- - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
ANNOUNCE - FAQ: Sources of EMC Safety Compliance Information, 30th Issue
FAQ: Sources of EMC Safety Compliance Information This is to let you know that I have just posted in two parts the 30th issue of the above FAQ to the newsgroup for regulatory/compliance matters and EMC and safety specifications and testing, sci.engr.electrical.compliance (s.e.e.c). The message IDs are: Part 1: 908460602...@lyons.demon.co.uk Thu, 15 Oct 1998 14:10:02 GMT Part 2: 908460797...@lyons.demon.co.uk Thu, 15 Oct 1998 14:13:17 GMT The FAQ is archived at the following URL: http://world.std.com/~techbook/compliance_faq.html and the latest version should appear there in the next few days. The textfiles may be accessed at: Part 1: http://www.lyons.demon.co.uk/seecfaq1.txt Part 2: http://www.lyons.demon.co.uk/seecfaq2.txt Hope you find the FAQ useful: suggestions for additions or corrections are welcomed. -- Bill Lyons - b...@lyons.demon.co.uk / w.ly...@ieee.org (maintainer of the s.e.e.c FAQ) http://www.lyons.demon.co.uk = Claude Lyons Limited Brook Road Waltham Cross Herts EN8 7LR England Voltage and Power Control - Precise Electrical Instrumentation Tel: +44 1992 768 888 Fax: +44 1992 788 000 Telex: 22724 CL LTD G email: i...@claudelyons.co.uk URL: http://www.claudelyons.co.uk =
