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Pow-M100 PRO not charging after switching from 12v system to 48v system.

slayer666

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I had this mppt charging two 12 volt lithium iron phosphates and it was working fine. Today, I got a 48 volt inverter and configured 4 batteries for 48 volts and it doesn't seem to be charging anymore. It shows 42 volts coming in from the solar panels but it does not show any watts at all and the charging indicator is not on. I don't know what I may have done wrong.
I thought it might have been because I top balanced all the batteries before I linked to them together so maybe it wasn't charging because the batteries were all ready full. But, I put a hair dryer and a refrigerator on the inverter to bring the batteries down and they came clear down to 95 or 96% soc and the mppt still showed nothing. Each battery BMS also shows me that they are not receiving a charge anymore. I'm really scared I might have fried something but, I'm pretty damn sure I did it all by the book. Any help is appreciated. Thanks gentlemen.
 
You can't charge a 48v battery with 42 volts.
Right. Thank you. I figured it out yesterday. Started reading the manual on it and it said that you need to have at least 72 volts to do 48 volt batteries. I'll have to configure the solar panels in series to bring my voltage up a bit, correct?
 
Thank you. I appreciate it. While I've got you here maybe you can answer something else for me. What I'm doing right now is using four 12 volt lifepo4 batteries in series to make the 48 but I just got a 24 volt inverter that's a lot higher quality and higher Watts than my 48 volt inverter is. I have this type of battery balancer in the picture below and I was wondering if I put those batteries in series parallel or parallel series to turn the four of them into a 24 volt battery, could I still use this battery balancer on them?
 

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I can't read any spec's so I don't know but it doesn't extrude confidence. I don't have any direct experience with quality balancers so you may want to ask others. Does the decription indicate is for balancing multiple 12v batteries? Like this one?
https://duckduckgo.com/?t=ffab&q=li...edia-amazon.com/images/I/61U13-IAXpL._AC_.jpg

Many are designed to balance individual 3.2v cells not prepacked 12v batteries. Be sure it can.
 
I can't read any spec's so I don't know but it doesn't extrude confidence. I don't have any direct experience with quality balancers so you may want to ask others. Does the decription indicate is for balancing multiple 12v batteries? Like this one?
https://duckduckgo.com/?t=ffab&q=li...edia-amazon.com/images/I/61U13-IAXpL._AC_.jpg

Many are designed to balance individual 3.2v cells not prepacked 12v batteries. Be sure it can.
Yes. It's like the one you link. I was just told by someone that you need to balancers if you do four batteries to make 24 bolts. One balancer on each string. This balancer has enough wires to do four batteries but, I'm not sure if you can connect it a 24 volt system like I'm talking about.
 
The one in the link indicates it can do 24v but I'm not sure it can do two 12v in series. It would need a balance lead for each 12v battery. Try to get a manual for it.
 
The one in the link indicates it can do 24v but I'm not sure it can do two 12v in series. It would need a balance lead for each 12v battery. Try to get a manual for it.
I have the manual and in two places it says that the balancer can be used in series or parallel with two to four batteries at once. I don't know if it's okay to hook it up in series and parallel like you would be doing with four 12 volt batteries to make 1 24 volt battery.
It's number five in the picture.20250611_152458.jpg
 
those batteries in series parallel or parallel series to turn the four of them into a 24 volt battery, could I still use this battery balancer on them?
You need a 24v balancer, the HA01, on each two battery string, with each string connected in parallel. Dont use the HA02 with a 24 volt system.
Screenshot_20250115-215837_Chrome~3.jpg
 

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