256 ° emt with no conductors in it

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jim gage said:
When I returned to begin the hunt for the problem, we started with a feeder conduit wiring j-box due to a high resistance to ground reading from the de energized panel neutral and water pipe in the apartment. Crawled through the nasty attic opened the j-box and found nothing. I crawled out whet down to my service van for a drink of water and did a little more testing at the meter stack . I was sure I would find nothing but did it anyway. I clamped the conduit that had current on it and it was still there of course but it was only 4 amps at this time. At this time I noticed the main was not properly secured to the 1880 brick building and was putting diagonal torque on the connection busses.
Tested neutral to main line voltage in bank 1 meter stack had perfect balance then I tested neutral in bank 2 to main line voltage and this time I had 121v A phase and 123v B phase.
Same one bank 3 meter stack. Bingo light went on just like in the cartoons!
Continued test from bank 2 to line and pushed slightly on the main enclosure and it went back to balanced voltage. Called LPC power they came out and removed meters so I could access buss connection bolts and they were all loose in both section 1 and 2. In my opinion they were never tightened during original installation orver 30 years ago. I got 9 turns out of every one on both sections re-energize gear all issues of unbalanced voltage and conduit current and ground current were solved. Due to observations of arching on A and B phase we have a meter bank and main to replace some time in the near future. Just wanted to say, sometimes even when all things point to a bad piece of service bussing and you cannot find anything wrong with meter testing look around and if something in the install isn't look right just give it a little tug or a shove you may be surprised what you will find after that.
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Temporarily adding more load also makes some problems reveal themselves better. (sometimes best to not do so with the regular load connected though, especially if you are tracking down a suspected bad neutral issue).
 
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