Being an intuitive person myself; I wouldn't want to discount "feel". Especially since EMC is a topic that often can't be quantified. However, before committing to something that may cost money and possibly be a safety issue; I'd have to see something to back up that feeling.
For normal test setups, the GRP is perfectly adequate. So, you really have no compelling reason to change... So...I would put the burden of proof back onto your co-workers. I would ask them to explain why they feel the way they do. Most people who work by "feel" have experience to back up their feelings. Ask them to justify the ground rods either by experience or on technical grounds. Obviously, your own feeling that you don't need to change is based upon your experience. The only time I would go strictly on gut feel with nothing to back it up is when there is no other option, or if there is something great to gain by taking the risk (a.k.a. gambling). I don't think that you're in that situation. You apparently already have a test setup that is working fine. So I would think that you would need a little proof to change what you have. I hope this helps. Chris Maxwell Design Engineer Nettest From: Chris Wells [mailto:[email protected]] Sent: Wednesday, April 06, 2005 10:31 PM To: Chris Maxwell; Robert A. Macy Cc: [email protected]; [email protected] Subject: Re: EMI ground plane reference versus NEC single point earth bonding Hi Chris Well the pressure is from competing EMC gurus who think that the ground rods "feel" like the right thing to do. They have not been able to lend much logic to the discussion. On the other hand I have a lot of NEC types that have been raising red flags like myself and we have been raising red flags about safety. No I would not say there is anything realy unique about the 3 phase power topic other than the installation class is often III. I am presently designing a Power Quality Meter and need the power supply and metering circuits to take quite a 6KV surge.......and the EFT is 4KV. I also push the RF radiated immunity beyond 20V/M with modulation. So far that has not been a problem. Chris 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 [email protected] Instructions: http://listserv.ieee.org/listserv/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
