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How can this system work...

How can this system work...

How can this system work...

(OP)
Dear all!

A simple problem (it's not a homework I promise!).

I have

4 x 12V 85Ah batteries.

1 x 12V 85W solar panel

2 x 12V solar charge controllers

1 x 24V solar charge controller

How can I power a system with 24V night and day assuming the power consumption of the system is not draining much power. I unfortunately cannot change the solar panel.

Thank you in advance, and looking forward to hearing from you soon!!!



RE: How can this system work...

Short of some way of switching a single 12V charge controller frequently back and forth between the two two-battery banks, I see no way to solve this with out further purchases.

A scheme that switches the charge controller output back and forth between the two two-battery banks in parallel, about every 5 minutes, all solar day, would be needed.

Otherwise use a (new)step-up charger that can take the 12V from the panel and and charge a 24V battery bank. Or procure another identical panel and use one panel to charge one battery and the existing one to charge the other battery - each using one of the two existing 12V charge controllers.

Keith Cress
kcress - http://www.flaminsystems.com

RE: How can this system work...

as keith says, or similar:

do we assume the 85w solar panel is enough to power your 24v load? if so, do we assume avg load is about 30watt or 1.5amp #24vdc?

then use 1 batt, 1 12v charger, and 1 12v->24v converter like:

http://www.secamerica.com/products/converters/620....

or give more details :)

RE: How can this system work...

(OP)
Thank you very much for the answers.

I will try the step up transformer! I hope it works!!!

RE: How can this system work...

Your converter seems a bit thin for this application. I would have expected something along the lines of 8.5 A charging current. The 85W panel is only going to produce about 3.5 A on a good day, but your converter is limited to 3A. You've never stipulated your power draw, so that would subtract from your charging rate. Even ignoring that, a fully depleted battery could potentially 5 days to fully recharge.

TTFN
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RE: How can this system work...

(OP)
I'm planning on installing the step up after the batteries... to power my system, which draws around 1A of current

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