How do you figure this thing? I've used a number of online 'wire gauge calculators', and I've contacted sources for 'expert advice', and I'm getting told everything from 22ga on up to 12ga. Not sure which calculator and/or source to believe.
How do you figure this thing? I've used a number of online 'wire gauge calculators', and I've contacted sources for 'expert advice', and I'm getting told everything from 22ga on up to 12ga. Not sure which calculator and/or source to believe.
Thanks again. The input is great.
The calculation depends on what your "source" voltage is and the minimum voltage needed to run your load.
We can start with 12volt as your source and limit it to say a 2% drop and come up with a wire size but it really depends on what the 2 voltages are in my first statement.
Is that from the panel to controller or to the light? I once has a SL something till lightning took it out. Believe it is a PWM controller. Peak power point voltage of panel will be over 17V and the battery could be up to 15V. PWM is like a direct connect. The panel will drop down to whatever the battery is. That means even a 2V loss in the wires makes absolutely no difference. In this case those tables aren't worth a hoot. A 160 feet of #20 is 1.6 ohms and at 0.21A is only a third of a volt. If it is to the lamp from the controller that isn't much of a drop either. I'd be looking at structural integrity of the wire as the deciding factor.
The calculation depends on what your "source" voltage is...
Since this light would need constant power, I assume that I would fuse the run directly from this battery to the light. If that's not the correct way to do it, please let me know. The battery tests at 14.6 volts.
Originally posted by SunEagle
...the minimum voltage needed to run your load
Would that simply be 12v? If not, how do I find this voltage?
Since this light would need constant power, I assume that I would fuse the run directly from this battery to the light. If that's not the correct way to do it, please let me know. The battery tests at 14.6 volts.
Would that simply be 12v? If not, how do I find this voltage?
I would use 12V as my reference voltage for the drop calculation even if the battery will sometimes be above that value it makes the wire size a little bigger.
Yes install a fuse between the battery and load. Size it to protect the wire.
Is the light an LED with a driver circuit, or a simple resistor current limit, or is it an old school incandescent bulb ?
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