I have a 9V AC-DC adapter...i need to find out the +ve and -ve wires of it...there are two wires...but how to identify them?
or temme if i m wrong in my basics!!! :)
2007-04-06 17:53:34 · 4 answers · asked by haridravid 2 in Education & Reference ➔ Higher Education (University +)
just touch each wire to the positive and negative of a battery, and whichever way it gets power, you will know which one is the power, and which is the ground.. (it won't harm the AC-DC adapter with a 9v battery)
2007-04-06 18:02:07 · answer #1 · answered by Randy from AR 2 · 0⤊ 0⤋
Set multimeter to measure DC volt. Remove the insulation sleeve from both wires. Connect meter RED probe to wire marked 300V. Connect meter Black probe to white wire. Plug adapter to power source. If meter shows + voltage reading, The RED probe touched is positive. If meter shows - voltage reading, The RED probe touched is negative..
2016-05-19 01:41:50 · answer #2 · answered by ? 3 · 0⤊ 0⤋
with a volt meter
put the red lead to one wire and the black lead to the other wire, if you get +9v the wire connected to the red lead is the hot wire. If you get -9v the wire connected to the red lead is the ground.
2007-04-06 18:02:32 · answer #3 · answered by Anonymous · 0⤊ 0⤋
usually one of the wires has a white or red line on it and that would be (+). or you can use a DMM or VOM to check it
2007-04-06 18:00:43 · answer #4 · answered by oldguy 6 · 0⤊ 0⤋