Karl Schmidt wrote "Failing to realize that a wire connected to ground at one end is not at ground on the other end, if it is carrying current is endemic."
Some years ago, while I was still at NIST, we held an international conference to address the building design/construction requirements necessary to create "world class" research facilities (which is a warm and fuzzy phrase, but never mind!). Every participant told stories about the problems they had experienced with ground-current induced noise. To the shock (so to speak) of the NIST staff who were present, an engineer from our own plant division confessed that until recently we had an extreme case in a laboratory building where the emf measured between neutral (the white wire in U.S. 120vac circuits, what we are accustomed to think of as "ground") and earth was as much as 30 volts depending on the time of day and the particular pieces of electrical equipment in operation. Yikes! I had often heard stories of problems in industrial settings; I never suspected a "clean lab" environment could be just as bad. So can a shop. Regards, Kent ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
