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Topic Title: Trapezoidal Metal roof-electrically live
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Created On: 21 February 2014 03:04 PM
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 21 February 2014 03:04 PM
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Hi All,
Has anyone experienced live contact with a metal roof fitted with solar pv panels, I have been called to two installations whereby there is a live current of between 35 - 65v a.c. when measured direct to earth via an aluminium ladder placed against the edge of the roof sheets.

Both roof installations are superimposed onto wooden buildings as the manufacturers instructions have been followed i.e. there is no requirement to earth the sub-frames or panels to an earth connection

can anyone throw any light on the situation

 21 February 2014 03:19 PM
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What type of instrument have you measured this voltage with?

In cases such as this, it is often useful to obtain a voltmeter with a low input impedance to check that the voltage is 'real' and not due only to combination of stray coupling and a voltmeter with a high input impedance.
 21 February 2014 10:25 PM
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I take it that the metal roof has no LPS installed? Otherwise that would have brought any potential down.

Lack of planning on your part doesn't make it an emergency on mine....

Every man has to know his limitations- Dirty Harry
 22 February 2014 12:42 AM
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I think the biggest clue here is that you are measuring an AC voltage.......

The solar panels themselves produce a DC voltage .... so.....
 11 December 2014 03:22 PM
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Radio/transmission energy perhaps?

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