Mppt's and Charger

[Rocketman]

Hello everyone,

I am getting ready to start this new build my own LiFePO4 battery, and last night I had a thought on charging the batteries for testing.

I will be getting a Amazon 30V/10A CV/CC charger. I want to run some capacity tests before installing in my RV. Draining is no problem... For Charging I figured I would just use the CV/CC charger, then I got thinking...

Could I attach the CV/CC charger to my MPPT solar controller and use the MPPT to charge the battery???

The charger at 30volts & 10Amps will produce 300 watts that will go through the MPPT and get converted to about 20 Amps.
Whereas just connecting the charger @ 14.5V it will charge at 10 Amps,

Will this work - my thought process says yes the MPPT will not care if the power coming in come the sunlight or from the charger.

Thanks

 

[snoobler]

One can find many examples of powering an MPPT with a source other than a solar panel.

Provided your MPPT can accept the 30V/10A and deliver >20A to battery, you should see a boost. It may not get all the way to 300W, but it should be more than 145W.

 

[lexio]

One can find many examples of powering an MPPT with a source other than a solar panel.

Provided your MPPT can accept the 30V/10A and deliver >20A to battery, you should see a boost. It may not get all the way to 300W, but it should be more than 145W.

hi snoobler my system 30v 10ah bench and a tracer 4210a is working like a champ 23 ah charge no problem and you can check the scc really nice.
but now the following can i connect my bench power supply 30v and a 310w 36v solar panel together so i create a system that can charge 40 ah
voltage is not the problem for the 4210 (100v max)
just being cheap
or is there a other way of a cheap 50~100 ah 12v fixed controllable charger for the RV. Cant have any more solar panel on my roof.
thanks

 

[snoobler]

Ah is Amp-hour - it's a measure of CAPACITY at a given system voltage. Amps are current. I assume you mean Amps when you say Ah.

You could series them, but you'd be limited to the lowest current of either device, so when the panel isn't at full power, the power supply will be limited.

You could possibly parallel them, but I would be hesitant due to the higher voltage panel.

 

[A.Justice]

One can find many examples of powering an MPPT with a source other than a solar panel.

Provided your MPPT can accept the 30V/10A and deliver >20A to battery, you should see a boost. It may not get all the way to 300W, but it should be more than 145W.

I know this thread is a bit old, but I wanted to do this. I have a Victron 100/30, and two 32 volt, 10 amp switching mode bench power supplies (I run them at 9A rather than the 10.1 they are capable of, just to be safe). I figured instead of charging at ~260 watts (14.4v * 9 amps, * 2 PSU's), I could get almost 600w if I ran it at 32v and 9 amps. Do you know if this is okay to do? I don't want to fry anything, and I don't really have the budget to get another Victron.

If you could please provide a link or keyword to search for the "many examples" of this, I would be much obliged. I was able to find people doing it with a PWM (although I'm not sure exactly WHY they are using a PWM, there isn't any gain), but not an MPPT.

 

[lexio]

don`t have a link but de max in put of a 30 A charge controller is some where around 360 watt.
12v*30A i think connecting 2 bench power supplies at full throttle will be to much.


set both of them to 6A 30v *2 == 360watt
the only problem i have seen is when de mppt starts the float charge, voltage of the bench power supplies will drop to the float charge level e.g. 13.6 v