How To Tell Which Wire Is Positive Solar Panel

Only your volt meter will tell you the truth.

How to tell which wire is positive solar panel.

Make sure that the locking tabs snap in for a firm connection. There is no color code standard for solar pv panels like there is for ac systems. Wiring solar panels in parallel causes the amperage to increase but the voltage remains the same. Actually there is a color code standard for dc pv systems and as the nec code book does not specify ac or dc the color code applies equally to both such systems.

When stringing panels in series each panel additional adds to the total voltage v of the string but the current i in the string remains the same. To measure across the solar panel terminals or wires put the red positive meter lead on one side and the black negative on the other. Set the volt meter to read dc volts. The bare end of the positive extension wire will now be of positive polarity.

Connect the negative wires together in the same fashion and the wires off the last panel in the parallel circuit are connected to the battery. When stringing in series the wire from the positive terminal of one solar panel is connected to the negative terminal of the next panel and so on. Another way to find the polarity of the solar panel is to check with a volt meter. Connect this cable to the mc4 male adaptor.

With parallel solar panels the positive terminal from one panel is connected to the positive terminal of another panel and the negative terminals of the two panels are connected together.