while testing this theatre, i attempted to get a Zs from an emergency exit sign. The steel conduit is being used as cpc.
when i connect my three probes to l,n,earth i'm getting 110v on the screen and when i press test it comes up with about 160 ohms.
i put a voltmeter across and found 110v between L and E but 230v between L and N.
could this be a poor connection on the steel conduit cpc and if so, why does the voltage drop to approx 110v
thanks...its a bit of a puzzle