Charging four 12v batteries wired in parallel

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chuckster
Posts: 109
Joined: Thu Aug 27, 2020 4:53 pm
Location: Meridian, ID

Charging four 12v batteries wired in parallel

Post by chuckster »

I am going to connect a 200w 12v "suitcase" solar system to charge my coach's house batteries and found a wiring diagram for 'perfectly balanced battery charging'. I am no electrician but it seems that the points it gives you to hook up a charger to batteries wired this way should be 12v, no? When I measure the voltage at battery C at the "+" and battery B at the "-" I read a little over 6V on my multimeter. I was expecting that the points the charger connect to would read 12V. Should I be connecting a 12v charger to a place that has 6V? This doesn't seem right to me.

I have attached the diagram I am referencing.
Battery connections.jpg
Battery connections.jpg (139.99 KiB) Viewed 79 times
Chuck in Meridian, ID
'01 Safari Zanzibar 3646 (side entry)
Cat 3126B / Allison MD3060
Magnum M-Series "Blue Max" chassis
Owner since 8/2020

ProCycle
Posts: 32
Joined: Sat Oct 03, 2020 1:28 pm

Re: Charging four 12v batteries wired in parallel

Post by ProCycle »

I can't think of any way you could measure 6 volts there unless you have four 6v batteries wired in series parallel.

That's what is in my Ivory - four 6 volt batteries.

You definitely do not want to put 12v charging current to a 6v battery or circuit.
Jeff
1997 Serengeti Ivory 3740 Cat 3126 Allison

chuckster
Posts: 109
Joined: Thu Aug 27, 2020 4:53 pm
Location: Meridian, ID

Re: Charging four 12v batteries wired in parallel

Post by chuckster »

ProCycle wrote:
Tue Apr 20, 2021 12:32 pm
I can't think of any way you could measure 6 volts there unless you have four 6v batteries wired in series parallel.

That's what is in my Ivory - four 6 volt batteries.

You definitely do not want to put 12v charging current to a 6v battery or circuit.
Jeff,

You’re absolutely right. I had assumed they were 12v because the voltage is not marked anywhere. I looked up the model and sure enough they are 6v. Measuring across an individual battery’s posts does produce a 6v reading. Upon closer inspection, these are wired series/parallel to produce 12v. Lesson learned BEFORE the mistakes...inspect very carefully! :shock:

Regards,
Chuck in Meridian, ID
'01 Safari Zanzibar 3646 (side entry)
Cat 3126B / Allison MD3060
Magnum M-Series "Blue Max" chassis
Owner since 8/2020

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