Asked in Modification of Old Electrical Work
How do you know which cable is positive and which is negative in a charger adaptor?
November 27, 2008 11:43AM
The best way is doing a continuity test with a multi-meter. On most meters the sign
is the Greek letter omega,,, set meter to continuity and touch both probes together,
set meter so you get a sound when they are touched together. Now place one probe
on the plug end and one on the service end, this will tell you which hole,, or inner or
outer sleeve is neg. On the outlet plug end 120v the larger of the two is neg.