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taylor-made avatar image
taylor-made asked

Smartsolar MPPT 100/50 Reverse battery polarity

I have been gathering components to build a solar system for my travel trailer next spring. I decided to head out this weekend with a couple panels and my new 100/50 controller for a late season camping/testing trip.

Found out a little too late that the outside ‘solar ready’ plug on my trailer was wired backwards from the factory. I am kicking myself for not checking it first.


My MPPT is now dead, absolutely my mistake. My question is whether this is repairable by Victron or is the unit toast?

I have a trouble request in with the distributor but haven’t heard back just yet. Mainly I’m curious what I should expect.

Thank-you,

Rob

MPPT Controllers
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Alexandra avatar image
Alexandra answered ·

@Taylor-Made

Not repairable unfortunately the fuse is internal. I have seen a couple of escapes when it was caught before solar was connected though. And once where the battery cable fuse blew first.

The only reverse polarity that will kill it is battery.

Reverse polarity on solar you should 'get away' with it as long as the battery was wired correctly.

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Kevin Windrem avatar image
Kevin Windrem answered ·

If you are plugging the output of the MPPT controller into the "solar ready" connector and that is connected to the battery inside the trailer, check the fuse in the bottom of the MPPT controller. It's there to protect against reversed battery voltage.

These are often in-line fuses buried deep in the wiring harness. To check for problems there, measure the voltage at the "solar ready" connector. If there is battery voltage present, you do not need to dig further. But if it's 0 volts, then trace the wiring back to the battery to find the fuse that may be blown.

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seb71 avatar image seb71 commented ·

check the fuse in the bottom of the MPPT controller. It's there to protect against reversed battery voltage.

No fuse can protect against reverse polarity.

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