Re: [PSES] Ground Plane Grounding in the Immunity Lab
Grace, Our lab is used for testing of ITE products to the IEC 55024 (CISPR24) immunity standard. We built ours from sheets of 1/4 (6mm) 5052 aluminum, screwed down onto 1 (25mm) plywood, with the plywood then fastened to the building floor. (Our products are large, heavy, rack-based systems, and this aluminum is hard enough to prevent the rack casters from doing any damage to the plate.) A 4 (10cm) wide backing plate is placed under each butt joint, and fasted to the plates with countersunk screws about every 4 along the joint. This insures good electrical continuity across the entire plane. The backing plate does require the plywood to be routed/notched at the butt joints, to accommodate the extra thickness of the backing plate. We have two such floors, one which is about 15 years old, and have had no issues with them (electrical, mechanical, auditors). These are grounded to the building steel. One uses a flat braid, the other uses 6 gauge wire. John D. Flavin Teradata TCP Engineering 17095 Via del Campo San Diego, CA 92127 john.fla...@teradata.commailto:john.fla...@teradata.com V: (858) 485-3874 F: (213) 337-5432 From: Grace Lin [mailto:graceli...@gmail.com] Sent: Friday, August 23, 2013 6:04 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Ground Plane Grounding in the Immunity Lab Dear Members, Could you please share your experience and/or knowledge for the ground plane grounding in the immunity lab? We plan to layout a L shape ground plane in the 24' x 18' area for ESD, etc. tests. The corner of the L shape is right next to a 10 wide building collar. Is a ground strap tied to the collar good enough? Do we need (copper) ground rods? If yes, what is the minimum length (deep)? What is the recommended space between rods? How to choose metal sheet material (galvanized steel, stainless steel, etc.)? When weldering the metal sheet, is there anything that need to be cautious? Thank you very much and look forward to your help. Best regards, Grace Lin - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.orgmailto:emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.netmailto:emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.orgmailto:mcantw...@ieee.org For policy questions, send mail to: Jim Bacher j.bac...@ieee.orgmailto:j.bac...@ieee.org David Heald dhe...@gmail.commailto:dhe...@gmail.com - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com
[PSES] CISPR 22 telecommunication port testing question
I need to test some telecommunication ports for conducted emissions according to the methods in Annex C of EN55022:2010. I am testing floor-standing equipment. The question I have relates to the figures shown in Annex C, vs. the test setup figures shown in the body of the standard (Figure 8, arrangement for floor-standing equipment). Figures C1, C2 and C3 in Annex C all show the EUT spaced 40cm from the groundplane [note 1 in the figure says Distance to the reference groundplane (vertical or horizontal)]. Figure 8 shows the EUT on an insulator (maximum 15cm thick) on the horizontal ground plane. Which figure governs the setup for telecommunication conducted emissions for floorstanding equipment, Figure 8, or Figures C1, C2, C3? I'm relatively new to testing telecom ports for conducted emissions, so is there some significance to the 40cm spacing show in Annex C? John D. Flavin Teradata TCP Engineering 17095 Via del Campo San Diego, CA 92127 john.fla...@teradata.com V: (858) 485-3874 F: (213) 337-5432 - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com
BSMI requirements for EMC Test Reports
Our lab is working on becoming a BSMI recognized EMC Lab via the APEC Tel MRA to which both NIST (USA) and BSMI (Taiwan) are signatories. Does BSMI have any specific requirements regarding what information must appear in an EMC Test Report for ITE? If so, where are these documented? I have looked through CNS13438, and the only information I see is that the 6 emissions closes to the limit must be recorded, and that a measurement uncertainty must be included. We have seen test reports issued by other labs that list all internal oscillators, and others that do not. Is this a requirement? John D. Flavin Teradata TCP Engineering 17095 Via del Campo San Diego, CA 92127 john.fla...@teradata.com V: (858) 485-3874 F: (213) 337-5432 - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher j.bac...@ieee.org David Heald dhe...@gmail.com
Radiated Emission Measurements above 1GHz
We have copies of AS/NZS CISPR 22:2006 and CNS 13438:2006, both of which show radiated emission limits in the range 1-6GHz. Both reference CISPR 16-1-4 for the description of the test site. (Our copy of EN55022:2006 does not show any such limits.) A few questions: Has the CISPR test site for 1GHz been decided? Has the validation method for the site been decided? If the test site or site validation method is still not settled, how does one test to the limits shown in these two standards? John D. Flavin Teradata TCP Engineering 17095 Via del Campo San Diego, CA 92127 john.fla...@teradata.com V: (858) 485-3874 F: (213) 337-5432 - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Placement of LISNs for Conducted Emissions Testing to CISPR22/FCC part 15
Our company sells ITE systems that are housed in commerial 19 racks. The system is designed to be fault tolerant and redundant, so each rack has two AC mains cords. We do our own EMI certification testing (we're an accreditted lab), and our typical EUT consists of two of these rack, so there are 4 AC Mains cords to test, which we connect to 4 LISNs. A modified version of this system is now in the works, where the dual AC mains cords are replaced by multiple cords (with lower current per cord). The design now would have 10 AC mains cords out of one rack, and 8 from the other. This means the two rack EUT would have 18 AC Mains cords to test. In a perfect world, where cost were no object, we would have 18 LISNs, since this is the most efficient for testing -- set it up once, and test everything. Our question is how to place a relatively large number of LISNs and satisfy the standards' requirement of the 80cm spacing of the EUT and LISN. Specifically: 1) Are we allowed to place LISNs around all sides of the EUT, maintaining the 80cm spacing (i.e. have LISNs at the front face of the EUT, and run the mains cord from the back to the LISN)? 2) Are we allowed to stack LISNs on top of each other, as long as the LISN is bonded to the ground plane? Since we have to test each cord in turn, we could reduce the number of LISNs by combining a number of the cords not currently being tested through a second (or third) LISN. The downside of this is having to re-plug the cords after each cord is tested, which requires shutting the system down and restarting, which is a non-trivial task (and takes longer than it does to test one cord). John D. Flavin Teradata TCP Engineering 17095 Via del Campo San Diego, CA 92127 john.fla...@teradata.com V: (858) 485-3874 F: (213) 337-5432 - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
