[RE-wrenches] Induced V&I from overhead HV transmission lines

[Greg]

Rebekah and Jerry,

If I'm understanding R's post below, at that particular install you 
could kill the disco for the inverter and still have 12 kV at 1 amp 
running around.  Call me a worry-wort but that sounds like a _pretty 
important blind spot_ for us mortals to be aware of.  Maybe the fact 
that it was a 5 MW installation would keep less experienced people from 
getting hurt but I'd sure like to see some good sized placards mounted 
on the front gate and at the disconnects, inverters etc. warning of the 
risk present even with a locked out/tagged out disco.

Greatly appreciate you posting this Rebekah, I doubt I would have 
thought of this otherwise.

Greg Egan
Remote Power Inc.
> Hey Jerry,
> If I remember correctly - it was about five years ago -   it was a little
> complicated because the utility was doing the witness test where they pull
> one phase and leave the other two connected, then test that there is no
> current on any phase (because the inverters should shut off when one phase
> drops). So two phases were still fully connected to the utility power, and
> there was current flowing on those conductors, not from the PV array but
> induced from the higher voltage lines. The inverter did shut off, but the
> utility was still measuring over 1A  (at 12.47kV). I don't think we would
> have noticed except that the utility was specifically looking for the lack
> of current on the lines at that moment. I don't know what the high voltage
> lines were, maybe 100 kV and not that far above the PV system lines?

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