Continuity query - Can anyone explain this?
Circuit is a simple 12v DC, wired as follows -battery pos to bulb to spst switch back to battery earth. Testing with DMM in the dedicated audible continuity mode.
With switch open, all points from battery pos up to the switch read continuity as one would expect.
If one closes the switch (live circuit) repeating the above test gives a negative, no continuity result - which i understand to be correct as continuity testing should be done on non-live circuit.
BUT... if I then swap the DMM probes over (neg DMM to Battery pos) (still on live circuit) all points on the circuit now read continuity (beep)
Also this situation occurs just testing across battery terminals - pos to pos and neg to neg no continuity, but swapping so DMM neg to battery pos gives continuity.