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A definitive answer about charging with a bench power supply through an MPPT controller.

A.Justice

Swears he didn't start that fire.
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This has been discussed quite a bit before, but there were very few reporting back as to what happened.

I have a Victron 100/30, and two Hanmatek 310 (32v, 10a) switching bench power supplies. My battery is a 12 volt Lifepo4, and I can charge at 20 amps total, using both supplies. I figured I could use the PSU @30 volts to charge through the MPPP at closer to 30 amps, while using the other PSU at 10 amps directly into the battery, 40a total, rather than 20a, much faster.

I plugged my PSU I to the Victron set at 30 volts, 10 amps, and had the victron set for 10 amps max battery charging. There was an almost immediate squealing out of an otherwise quiet power supply, while it tries to find the maximum power point. I shut it off. Set the PSU to 16 volts 3 amps max, and the victron at 1 amp. Still the broken electronics noise.

For what it's worth the power supply still works and has been charging it 10 amps for the past few hours with no problems.

If anybody has any advice as to what to do to fix this problem, or could explain what's going on that would be awesome.
 
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A CV/CC power supply does not have the I-V profile like a PV panel when PS hits CV limiting so they usually confuse the MPPT algorythm in controller.

Try one of these buck switchers on output of PS to get higher charge current from your PS. They are cheap.

 
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There might be problem with power supply.
I bought 2 different models to do the same thing and one works fine and the other one makes a high pitched noise so I don’t use it for that but bought a second one of the other type.

I set it to 24v and 8 amps and it worked fine going through a victron 75/15.

The other model that made noise works fine as a bench supply as long as iI keep less than 80-90% output.
I found all 3 power supply did not like running at 95+% so I backed them off to 200-240 w as they are cheap power supply and don’t want to burn them out.

HTH
 
You are trying to parallel psu dc output?
I was trying to use one to charge the battery directly through the terminals, and the idea was to use the MPPT and second PSU to speed it up. I only parallel then when I'm using both to charge.
 
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