P
paulk11
Afternoon. Did a PIR on a TT installation yesterday with some confusing results.
Ze/RA was recorded as 116Ohms so as expected thereabouts. When Zs was tested it was found to be just 1.01 Ohms and 0.97 Ohms at a several points with just a few reading high as expected. As Zs = Ze+(R1+R2), it seems inconceivable that it can be that low. I',m thinking an alternative earth has sneaked in somewhere; (possibly a link to a TN system somewhere nearby?)
Following the Zs test, the RCD (S Type) started tripping and also failed the RCD test. We're now in a position where the RCD will stay made for a while but keeps tripping out for no apparent reason.
My initial thought is to change the RCD and see how that effects things.
Any suggestions?
Ze/RA was recorded as 116Ohms so as expected thereabouts. When Zs was tested it was found to be just 1.01 Ohms and 0.97 Ohms at a several points with just a few reading high as expected. As Zs = Ze+(R1+R2), it seems inconceivable that it can be that low. I',m thinking an alternative earth has sneaked in somewhere; (possibly a link to a TN system somewhere nearby?)
Following the Zs test, the RCD (S Type) started tripping and also failed the RCD test. We're now in a position where the RCD will stay made for a while but keeps tripping out for no apparent reason.
My initial thought is to change the RCD and see how that effects things.
Any suggestions?
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