How to Get Connection from Solar panel
Back Side of The Solar Panel Junction Box and The Function of Diodes in it.
Today, i m going to show the back side of solar panel and its junction box. you will get idea that how to get connection from solar panel junction box.So here we go step by step
image ( below) shows junction box on the back side of the panel. you can see two diodes ( why diodes??? we will discuss later) and two terminal wire one of Positive (+) and other one is Negative (-) both wire will go to charge controller ten battery ( for charging purpose).
Note that this 60 Watts, 12 Volts, and 5 Amperes panel but . I am using it for 120 Ah battery with 12-15 A charge controller.
junction box (more clearly), this is loop system, as you can see, there are three terminal, that’s why we say that it is a loop. Also you can see two diodes which have connected in forward bias from solar panel to output battery charging.
Function of The Diodes in Solar panel junction Box
Actually these diodes have connected in forward bias for protection purpose. How Protection???? yes…let see how.
Suppose we are charging battery through solar panel. When battery is fully charged. then what will happen at night when solar panel is not active… in other words, battery will supply voltage to the solar panel again. but here we have connected a Diode
( From Solar Panel to Battery = Forward Bias)
(From Battery to Solar Panel = Reverse Bias) See fig.
So in this way the Diodes block the revers voltage from battery to solar panel. How to Get Connection From Solar Panel Junction Box.
In My Case,( 60 Watts, 12 Volts, and 5 Amperes panel but . I am using it for 120 Ah battery with 12-15 A charge controller) so here is three terminal wires
fig clearly show that we can get 12 Volts through the left one Negate and the right one positive.
in other hands, we can also get 6 Volts through the lift one Negative and The central Positive wire ( Between Lift (-) and Right (+).Note:
For Solar Panel wiring diagrams, Installation and Repairing , Check in the labels or Above tab “Electrical Wiring” Section. There are about 30 useful wiring diagrams under the “Electrical Wiring” Tab.
By: Wasim Khan
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