Smart Charger & Solar Panel conflict possibilities

Submitted: Tuesday, Oct 15, 2013 at 18:01
ThreadID: 104732 Views:2044 Replies:4 FollowUps:2
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At moment I run a 21A multistage smart charger, in to a 120ah deep cycle battery. I have recently purchased a 160w solar panel kit which I have test run with excellent results. I now want to tidy up all my wiring that is inside my toolbox(on the van) & permanent wire in the smart charger(as it will never move) and the only thing I want left as a clip on unit is the solar panels. By doing this, will the charge from the solar panels be affected & /or will the smart charger be affected?
Right now if the charger is left DC connected and battery is in float state and I turn the 240v off to charger, then all indicators on charger stay active as does the cooling fan at times.
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Reply By: Brian 01 - Tuesday, Oct 15, 2013 at 21:00

Tuesday, Oct 15, 2013 at 21:00
No reply after a couple of hours, so I'll try to help.
I will assume firstly that the charger is still connected to the battery but not on mains power.
There will be no conflict between the solar and the charger but the charger will be drawing some power if, as you say, it continues to have indicators operational even when turned off.
Whilst this won't cause any conflict, it will slowly drain the battery when no charge is applied from the solar. Maybe an isolator in one of the charger cables should be considered to stop this.
Second possibility:- mains on, no solar - no problem there either.
Third possibility:- Mains on, solar working - possible minor conflict between the two with regard to voltage sensing, but this is generally not a big deal and the batteries will charge.
If the charger is a reasonable size and is being used on mains power, then disconnecting the solar and just using the charger may be an option.
If on a generator, then try to get what you can out of the solar first and then top up with the charger, this will be time and prevailing Soc dependent of course.
I would suggest that you dispense with the clips and employ a decent plug in arrangement for the solar as just one lapse of concentration resulting in reversed polarity could be costly.
Hope this is of some assistance.
AnswerID: 519762

Follow Up By: kevmac....(WA) - Tuesday, Oct 15, 2013 at 22:36

Tuesday, Oct 15, 2013 at 22:36
funny you should mention the plug idea for the solar, have been toying with that since i was testing it.......Also thanks for the other information
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Reply By: Member - LeighW - Tuesday, Oct 15, 2013 at 21:30

Tuesday, Oct 15, 2013 at 21:30
Have you tried leaving the charger turned off for awhile, with the charger I have, if you turn off the AC the charger shuts down, ie leds fan turn off etc. If the charger has decent filtering capacitors in it, it may take a few seconds for it to shut down?

If it doesn't then you could install a switch to select either solar or 240V.

It is pointless to connect both the solar and 240V charger at the same time, as they will either partly share the load or one will take over, therefore your unlikley to lessen the recharge time.


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Follow Up By: kevmac....(WA) - Tuesday, Oct 15, 2013 at 22:38

Tuesday, Oct 15, 2013 at 22:38
Thanks for your info Leigh, will take all info on board.
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Reply By: kevmac....(WA) - Tuesday, Oct 15, 2013 at 22:42

Tuesday, Oct 15, 2013 at 22:42
There will always only be one charging unit running at any given time, is just that at moment everything is attached using clips, and this is what I wish to get away from.

If I understand you both correctly there should be no problem leaving my smart charger hard wired and having my solar unit detachable( in one form or another).
AnswerID: 519771

Reply By: Malcom M - Thursday, Oct 17, 2013 at 07:35

Thursday, Oct 17, 2013 at 07:35
What about a charger that also supports solar?

Not quite what you are after but I have two similar solutions on my truck/camper trailer.

1/ On the dual battery truck, I have a Piranha dual battery controller that also has a solar input. The controller sorts out what volts are available from where and does its business accordingly. Not an intelligent charger though.

2/ The camper trailer has a couple of 100Ah batteries connected to the truck via a Ctek D250 intelligent charger. This charger is a DC-DC charger so will overcome the voltage drop in the trucks cabling and still charge the batteries with its 5 stage charger.
The beauty of this charger is that it also has a MMPT solar controller built in so can take the solar cells, automatically figure out where the best power source is and intelligently charge the batteries.
As it has its own MMPT controller, you can bypass any of these on your panels and let the higher volts overcome and loss in the solar cabling.
Brilliant but it doesn't have a mains input though.

I don't carry a mains charger (although I own one) as I figure that between the ruck and solar, I should have power.

AnswerID: 519844

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