Electrical Wiring in the Home/Wire polarity


Hi Greg.  I have a tricke auto battery charger and the male cigarette plug broke.  I bought a replacement plug with wires.  I would like to splice the new plug to the charger (DC) side.  The charger has 2 wires: one with writing and the other one with a ribbing along the length.

The new (replacement) cigarette plug has two wires, one having a white stripe along the length of the wire, the other nothing.  To keep proper polarity, does the white stripe wire get connected to the ribbed wire, or visa-versa?


The wire connected to the center of the lighter is the positive and the one attached to the side is the negative.
If the charger is not marked positive  and negative you can take a digital volt meter and quickly find out.

Put the voltmeter on DC volts and connect the red to one wire and the black to the other. If the meter reads negative volts it means you have it connected it wrong. Reverse the wires.
When the reading is positive it means the wire the red is connected to is positive and the black is connected to negative.
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Electrical Wiring in the Home

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Greg Hughes


Troubleshooting electrical including appliances and HVAC.


34 years of experience.

Both college and tech schools in this field.

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