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chp avatar image

MPPT 100/20 bulk charge voltage seems low. Fridge turns off and on when changing from float.

I thought bulk charge voltage should be around 14.6V??? Victron Connect app shows the voltage at around 13V or sometimes lower when in bulk change mode.

My fridge turns off and back on when controller changes out of float mode. (it is connected to the load output on the controller)

MPPT - Solar Charge Controller
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2 Answers
WKirby avatar image

To add to what John said, the inrush current from certain loads is enough to trip the Load Output protection. I resets it's self, but it can be annoying.
There is a way around it by using an NTC to limit the startup current.

I once wrote a topic explaining it all including the workaround:

https://community.victronenergy.com/articles/2992/load-output-of-mppt-charge-controllers.html

Also see this thread here:

https://community.victronenergy.com/questions/1861/smartsolar-10020-load-switches-off-in-float-mode.html


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if inrush was the issue wouldn't you see this ever time the compressor cycled on? The issue only occurs when the controller changes state from float regardless of whether the compressor is running or not.

JohnC avatar image

Hi Chp. Bulk V covers the whole V-spectrum, all the way up to Absorb V (your target). You should be able to watch it rise progressively if it has enough power.

The LOAD terminals aren't really recommended for inductive loads like a compressor fridge. If you can live with it, carry on. But otherwise, wire straight to the batts. If you want to retain the batt-protect function, do that with a relay driven from the load terminals.

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