I have put in a radial to a bedroom only to find all the wires, earth neutral and live, are lighting the light on my screwdriver. The neutral and earth were not even connected to anything at either end. Yet were both registering a little light on my screwdriver. What gives?
Disconnecting said live made the problem disappear.
I changed the cables but the problem persisted. All the cables (1.5mm) in that conduit were activating the light on my screwdriver (80 to 400V).
I can't understand how this can be the case when the cable ends are not even connected.