how to identify a negative and a positive wire in a mobile charger?

Z

ZipzAp

New member
i am using this for an electro plating experiment. it is a mobile charger and has only one insulation each one is pure black and another one is black with faint white marks. could someone tell me which positive and which is negative.
 
R

rock

Member
The wire with the white marks SHOULD be the ground however to make sure use a volt meter set the dial to DC volts and touch the red probe to the black wire and the black probe to the other wire.

If the needle rises I am right, if it seems to want to move down then the polarity would be reversed.

I've used this method for years, 100% accurate.
 
J

Joseph

Member
Rock is right, but chargers will vary from time to time
because of 'conventional current flow". Conventional
current flow is what they thought at first what was happening
in a given circuit (electrons flowing from positive to negative).
We know now that electron flow is from negative to positive.
Test your meter (set to DC volts) using a known good battery.
This is a simple test that you can perform to show you exactly
what kind of meter you have. Place the red lead to the positive
terminal & the black to negative. If the meter is "true". it will
show a deflection from left to right, or a clean display (no negative
symbol). You can now check your mobile charger's polarity
accurately.

Remember, electroplating takes a good amount of voltage and
current to have the desired results. Low voltage and current will
take a while depending on what you want to plate and what's the
metal that you want to use to plate with.

I suggest that you visit your local library and read up on electroplating.
 
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