question

mikedefieslife avatar image

Battery voltage reading issues from 75/15 MPPT

I'm having more problems with MPPT 75/15 controller.

I'm now having problems with the controller giving a random battery voltage reading. The battery voltatage is 12.90v (read at the battery and as the controller itself) the controller software is reading it at 14.20. The battery been used to the tune of 20ah, so needs charging, yet the controller has gone into float mode and is not delivering any current.


Panel voltage is at 22v at the moment.

MPPT - Solar Charge Controller
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4 Answers
wkirby avatar image
wkirby answered ·

Did you check the fuse of the MPPT?

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mikedefieslife avatar image
mikedefieslife answered ·

Ah darn. I think that's it. Blown fuse. Forgive me for being so daft. I knew for sure the BlueSolar had spade fuse on the underside, as it's quite easy to see. I've never noticed the fuse on the Smartsolar, and so forgot about it.

Sorry for wasting everyone's time.

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Not a waste of time at all if it solves a problem! That's what this community is for.

mikedefieslife avatar image
mikedefieslife answered ·

Yep it was 12.9.

The problem is the controller. There is voltage coming in from solar but no current. No matter what I set the battery float or absorption level to be, the controller doesn't put out any current either.

I have tested that my setup (bar the Victron unit) is working correctly by swapping in a Prostar 30. Immediately it registered 12.9v at the battery (which Is what I was seeing with my multimeter) and began charging.

It seems more like another software glitch rather than hardware failure, but a reset via Victron Connect doesn't help. Is there a method of hard resetting the unit?

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Guy Stewart (Victron Community Manager) avatar image
Guy Stewart (Victron Community Manager) answered ·

Have you checked the voltage at the battery connection terminals of the MPPT with a multi meter?

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