Steve, were you referring this post to me? Regards, Doug From: [log in to unmask] To: [log in to unmask] Subject: Re: ESD ground vs Electrical ground Date: Friday, July 25, 1997 12:50 PM You confused me, I assume you mean EARTH ground versus electrical equipment ground?? If this is the case, either will be sufficient from both a personnel safety and ESD safety standpoint if installed correctly. If using earth ground by inserting a grounding rod through the floor into the earth, the ground rod must be electrically bonded to the electrical equipment ground (I believe this is a National Electrical Code requirement). This is especially true if personnel are working with electrical equipment (soldering irons, etc.) while connected to ground. If there was an equipment failure where a "hot" wire contacted an electrical ground (i.e. through the equipment chassis) that charge is going to seek the least resistive path to ground. If there was a lower resistance to earth ground, personnel could be exposed to lethal voltage. However ESD wrist straps/cords must have a safety resistor installed to limit current flow in case this happens. The wrist straps and cords should be tested daily to ensure that the resistor is functioning correctly. Basically if facility electrical ground is per electrical code, that's the best way to go from both a safety as well as convenience standpoint. You might want to ensure that there is very little difference between electrical ground and earth ground prior to committing to one method or the other. Hope this helps, if I am not clear on something, let me know and I'll elaborate more (the boss gets mad when I spend 30 minutes writing one E-Mail) Steve McBride Frontier Engineering Inc. *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To subscribe/unsubscribe send a message <to: [log in to unmask]> * * with <subject: subscribe/unsubscribe> and no text in the body. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************