# EMP Solar panel repair OR learn a new skill



## budgetprepp-n (Apr 7, 2013)

Keep in mind this is post SHTF

If an EMP were to strike it's not really clear what would fry and what might not. I have read in a few different places that the damage to the panels would most likely to be the diodes. 

So where are they? And can they be replaced by the inline ones I see on Automobiles? The older cars used them a lot. 
As this being a prepper forum there are probably more than few peppers that should know this. Me included 

What about charge controllers?
I'm not sure what is inside them,, Maybe an easy fix maybe not.

Not long ago I was looking an old school Ford F-150 voltage regulator. I know how it works (sort of) and it does the same
thing a charge controller does. 

Has anyone ever used an automotive voltage regulator for a solar controller?

They both keep the voltage at around 14 volts max. 
Both are D.C. 

Knowing how repair a solar set up could maybe make a nice trade to know. 

from what I understand a diode is keep the electricity from feeding back in to
the panel at night. sort of like a one way gate for electric. So then could I just by pass the diode and put 
my panels on a switch? Flip them on when the sun is shining.


----------



## paraquack (Mar 1, 2013)

The diodes on solar panels are to prevent a "back flow" of power from the battery into the panels when they are not 
producing any power. They are redundant if you are using a charge controller.
I've seen diodes listed for panels on e-bay for $5 for 3 diodes. As far as repairing a charge controller, you would need 
a lot of equipment that would need to be protected from EMP. Easier to have a spare controller or 2 protected from EMP 
and stored away.


----------



## Chiefster23 (Feb 5, 2016)

I posted the same question about the old vehicle voltage regulator a while back. Nobody knows. I wanted to test out the idea but I just never got an old regulator. If you have one, why not try it out and let us know if it works. In theory, it should be fine but I’m sure it wouldn’t be as efficient as a charge controller. But hey, it would certainly be better than nothing. 
And I keep a bunch of spare diodes in a shielded metal box on hand, just in case. And a small butane torch for soldering since I’m sure an electric soldering iron will not be working when/if the diodes are needed.


----------



## Elvis (Jun 22, 2018)

The diodes in solar panels run fairly high amperage so you'd want at least a 7 amp replacement diode. You can buy 10 amp diodes online fairly cheap.
The diode is there to keep the batteries from draining back through the panels. During times of no sun the panels would turn the electricity from the batteries into heat and drain the batteries. In a pinch you could jump (bypass) the burned out diodes and the panel will still produce electricity but you'd have to hook the panels to the batteries only when there is strong sunlight and unhook the panels when the sun isn't strong.

Automobile alternators use an electromagnetic field to strip electrons from the stator, The car's voltage regulator detects the operating system voltage and when the regulator determines that the voltage is low it will send at least 4v to the alternator's rotor creating the required electromagnetic field. When the regulator determines that the system voltage is high enough it cuts the power to the rotor off halting output from the alternator.

Short answer is no, you can't use an old automotive voltage regulator as a solar charge controller.

Just keep a spare controller around, You may be able to repair a PMW type controller but an MPPT controller is much more complicated to repair.


----------

