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rgormley
Senior Member

Joined: 22/02/2006
Location: Australia
Posts: 245

Posted: 01:54am 30 Nov 2013

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have a question you guys may be able to answer.

bit of reading to explain what i have done and found out....

my current setup is i have a home built 50amp 12/24V PWM solar regulator hooked to 6X Sharp 180watt panels. all works fine, the regulator has variable volt set point, i set at 27.2 and it does the job charges the batts up, then can see the old ammeter needle pulsing once the upper voltage has been hit. then it floats the batts with shorts burst (high speed bursts) and the batts stay at 27.2

OK So i wanted a newer charge controller, bought a "solar30" unit 30 amp 12/24 volt.

http://www.papsolar.ca/pdf/CM30.pdf

(i fixed the crappy solder joints by reflowing the heavy connections and added good quality dow-corning heat sink compound the the power transistors inside

-My panels are wired two in series and combined at a buss bar in the control box,
-The open cct voltage on a cool sunny day is hitting 58volts <<--- problem??

what i find is, the new unit will charge up to the set upper voltage (27.2v) and then will PWM charge for 1-2 minutes then go back to zero amps (turn of charge from panels) the voltage will sag (with invereter/load) to around 23v then it starts all over again.

ie: BUT it wont float the batts like my old PWM regulator does.

I did a experiment i substituted the panels and put a 20amp power supply as the input to the soalr regulator.
current limited to 5 amps,
set the input voltage on the power supply to 32 volts
took some batts of line. (for a quick charge test)

it performed perfectly, switched the power supply on. The charge current went up to 5 amps for 10 mins (batts came up to 27.2v as set on the solar regulator)
it then backed of the current to 1.5 amps or so and happiply pulsed the batts keeping around 27.2v.

SO THE QUESTION: is my panel voltage (58) to high for the new fancy solar regulator?

the regulator it is rated at 50v max input so i am pushing the max limit a little....

If so what options do i have (put back the old regulator i suppose?)

Thanks...
Edited by rgormley 2013-12-01

davef
Guru

Joined: 14/05/2006
Location: New Zealand
Posts: 499

Posted: 10:29pm 02 Dec 2013

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Just a suggestion ... load the panel down so that the voltage does not go above 50Volts and see if the controller works properly. Just for a test.

norcold

Guru

Joined: 06/02/2011
Location: Australia
Posts: 670

Posted: 11:04pm 02 Dec 2013

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If you want a newer charge controller suggest you look at the Plasmatronic range. Good OZ technology, heaps of features, but most of all reliability and they will look after your batteries. More expensive but bloody good gear. Not knocking the Chinese stuff, they`ll get there but the OZ gear has got there.

We come from the land downunder.
Vic

Warpspeed
Guru

Joined: 09/08/2007
Location: Australia
Posts: 4406

Posted: 11:58am 30 Dec 2013

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I suppose it does not really matter.

If the batteries are near full charge at the upper voltage limit, that means you need to stop charging "somehow" to prevent excess battery gassing.

How you do that, proportional PWM, hard on/off disconnect switching, or some kind of dump load all achieve pretty much the same end result. Further charging ceases.

The uloaded solar panels may go super high open circuit voltage, but unless that voltage is likely to damage the controller, it should not be a problem.

Cheers, �Tony.

KarlJ

Guru

Joined: 19/05/2008
Location: Australia
Posts: 1178

Posted: 01:36am 07 Jan 2014

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well another +1 for the PL20 have one myself thanks to Phills advice on my now crashed Phill Mill...(tower failure)

without being too blatant....these days i work for this mob www.apolloenergy.com.au, good aussie business and we can look after the little guys just the same as the big guys.

forum members $275 just call up and ask, tell them Karl said to do the premium pricing...(normally requires $50K+ a month spend to get)

Regards
Karl

Luck favours the well prepared

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