New 12v solar panel and output is up and down constantly, help

Hi guys

Just bought this exact panel and regulator set up 12v 120w

PLaced the charger on a 130amp Trojan 12v deep cycle which was charged to 12.7v, I connected a waeco thermo electric cooler and ran it from the morning. Checked it at 13:30hrs and the battery voltage was at 12.07v under load of the cooler. Disconnected the cooler, battery went up to 12.5v, put a DC clamp meter around the active and found only 1.2a going in. Panels in full sunlight (no clouds near the sun at the time). I then put a cigarette voltmeter in the battery box and watched the voltage readout, it would constantly flick between 12.5 to 12.7v then 13.5v then 12.7v every second. Its like the solar regulator is doing this. Any ideas? Doesn't sound right and the current should be more from a 120w panel?

Regards
Chris
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Reply By: oldtrack123 - Tuesday, Dec 16, 2014 at 16:53

Tuesday, Dec 16, 2014 at 16:53
HI Chris
I think what you find is that the battery is fully charged.
The regulator is Pulse width modulating [Switching the Solar input ON& OFF] in responce to the battery voltage rise & falls
The current you see is actually the average of the amps going in,not the max
Different brand /models regulators perform differently in that aspect some switch on & off very fast ,so you do not see those changes ,just steady readings which is still an average
I am surprised that a claimed MPPT reg does such slow PWM switching
Quality one are usually realy fast & have smoothing in them
Can you get to the actual solar panel terminals?
Either atte regulator or at the actual panels?
If so a load test can be done on the panels.
Will explain how, if yo can get there
It would also be a good idea to disconnectt the battery from the solar REG & the fridge & let it stand for a few hrs then measure the battery NO LOAD voltage.
Come back


PeterQ

AnswerID: 543058

Follow Up By: Chris85 - Tuesday, Dec 16, 2014 at 17:01

Tuesday, Dec 16, 2014 at 17:01
The regulator is waterproof and sealed but I can open the junction boxes on the individual panels.
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FollowupID: 829877

Follow Up By: Chris85 - Tuesday, Dec 16, 2014 at 17:03

Tuesday, Dec 16, 2014 at 17:03
Voltmeter on battery is now showing 13.0v
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FollowupID: 829879

Follow Up By: oldtrack123 - Tuesday, Dec 16, 2014 at 18:20

Tuesday, Dec 16, 2014 at 18:20
HI Chris
Is that with the battery disconnected from the panels???
If so, the battery is well & truely charged & that would be why the regulator was pulsing & the Amps were low
All would appear to be well


PeterQ
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FollowupID: 829884

Follow Up By: Chris85 - Tuesday, Dec 16, 2014 at 19:57

Tuesday, Dec 16, 2014 at 19:57
That's with the panel
Connected to battery
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FollowupID: 829892

Follow Up By: Chris85 - Wednesday, Dec 17, 2014 at 13:11

Wednesday, Dec 17, 2014 at 13:11
Thanks for your help. I'm still struggling as I ran the fridge for a while off the battery without solar connected. Under load the battery was 11.44v so I kept fridge connected and connected the solar panel. Under load the battery rose to 12.0v immediately and I measured the current on the active wire near the alligator clip, it was showing 1.5-1.8amps. Surely with the battery this low the current should be more like 6amps. Perfect sunny day with the panel in direct sunlight. I'm confused as I have a 110watt panel that will output close to 6amps without any issue (different panel and regulator)
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FollowupID: 829935

Follow Up By: oldtrack123 - Wednesday, Dec 17, 2014 at 13:44

Wednesday, Dec 17, 2014 at 13:44
HI Chris
Based on that
Two possabilities:
[a] A very sick battery, badly sulphated up ,[limits charge current ]
, but with no load appears to near fully charge, based on voltage. But has very little actual capacity
What type of battery is it??

[b] A faulty regulator

MY first step now would be to fully charge the battery by another means then connect the fridge & see how long it will run for & how fast the voltage drops
That will check the battery out

If that does not reveal the pronblem, we can go to the panel testing steps


PeterQ
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FollowupID: 829937

Follow Up By: Chris85 - Wednesday, Dec 17, 2014 at 13:54

Wednesday, Dec 17, 2014 at 13:54
Have tried on two batteries, one is a 130ah Trojan the other is a cranking battery with little use. Same symptoms
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Follow Up By: Chris85 - Wednesday, Dec 17, 2014 at 13:55

Wednesday, Dec 17, 2014 at 13:55
I also have a 75ah optima yellow top which is 1year old that I could try
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Follow Up By: Chris85 - Wednesday, Dec 17, 2014 at 14:08

Wednesday, Dec 17, 2014 at 14:08
I put the clamp meter on the active wires on each panel before the reg. one was showing 0.6amp the other 0.4amp which is before the reg
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FollowupID: 829941

Follow Up By: oldtrack123 - Wednesday, Dec 17, 2014 at 14:25

Wednesday, Dec 17, 2014 at 14:25
Hi Chris
You have either of two problems
[a] A very sick badly sulphated battery
Such a battery will only accept a very small charge current,but can appear to fuly charge [by voltage reading]
The trouble is it can have very very little actual capacity so the voltage will drop quickly under load
It is a flooded cell
To confirm, you have some options:
[a] get a Hygrometer & check the electrolyte reading I expect it will read DISCHARGED or very low 11.75>
Take it to a battery store & get them to check it out

If that is not the problem, we can proceed to test the solar panel & reg

PeterQ
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FollowupID: 829945

Follow Up By: Chris85 - Wednesday, Dec 17, 2014 at 14:31

Wednesday, Dec 17, 2014 at 14:31
I just tried on my optima and same current flow but the optima stays around 12.65 under load of the thermo cooler. I do have a battery load tester if that would be worth it?
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FollowupID: 829946

Follow Up By: oldtrack123 - Wednesday, Dec 17, 2014 at 14:33

Wednesday, Dec 17, 2014 at 14:33
HI Chris
Sorry, I did not think my post went through, so reposted

You say you have"I'm confused as I have a 110watt panel that will output close to 6amps without any issue (different panel and regulator"
Have you tried connecting that one to the battery with the fridge running?

If that one works OK, you possibly do have a faulty reg!


PeterQ
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FollowupID: 829948

Follow Up By: Chris85 - Wednesday, Dec 17, 2014 at 16:08

Wednesday, Dec 17, 2014 at 16:08
Yeh my other panel is 110watt and is putting ou 6.3amos, within 10min was down to 2.5amos and battery reading 13.1v. This would prove the other panel has issues. Just spoke to the seller who told me their mppt controller is set down to prevent anything blowing up when people use it. I said is the panel capable of 6amps they said yes but they have altered the regulator down. I said that's not what I am after as such low current isn't enough to keep the battery charged if I want to run anything off it. I'm taking it back tomorrow and they said if I'm really not happy I can have a refund. What they are saying doesn't make sense to me. Why buy a 120w panel that is regulated at 1.5amps
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FollowupID: 829960

Follow Up By: oldtrack123 - Wednesday, Dec 17, 2014 at 16:25

Wednesday, Dec 17, 2014 at 16:25
Hi Chris
Sounds like a load of Crap to me too
I suspect they do not know what the are doing either
Just a question, do the actaul panels have any specs on them [on the back]?
If so check for voltages given @both open circuit & at peak power. Or count the number of solar cells in each panels

PeterQ
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FollowupID: 829961

Follow Up By: Chris85 - Wednesday, Dec 17, 2014 at 16:32

Wednesday, Dec 17, 2014 at 16:32
Have packed it away but I did test each panel and was getting just under 20volts each. Maximum current output on the label said 3.37a per panel
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FollowupID: 829962

Follow Up By: oldtrack123 - Wednesday, Dec 17, 2014 at 19:25

Wednesday, Dec 17, 2014 at 19:25
HI Chris
As I suspected when I asked that question & based on their answer to yours
They are not 12V battery charging panels which should have an open circuit voltage of around 21V & ppp around 17V
THe panels do not have enough voltage to push any higher current through
THe PANELS ARE THE LIMIT.
Obviously another mob who do not have a clue & one that many purchaser get caught up in
But as Kelpi has said
Since it is a MPPT controller it can probably take 40V open circuit, you could series connect the panels & then get the full ouput of the panels into the battery .
BUT you would have a shade limitation IF one panel was heavily shaded ,you would get the sort of current you are now getting.

Why take the risk,of series connecting them???as you do not KNOW the Regulator MAX input voltage & could easily stuff it ....
Get A refund Or ask for true 12V battery charging panels with an open circuit voltage around 21V & a PPP voltage not less than 17V

PeterQ
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FollowupID: 829976

Reply By: Kelpie D - Wednesday, Dec 17, 2014 at 17:19

Wednesday, Dec 17, 2014 at 17:19
I have just gone trough the exact same thing -

http://www.exploroz.com/Forum/Topic/110295/MPPT_Controller_Question.aspx?ky=&sn=&p=%2fForum%2fDefault.aspx%3fpn%3d4

What the seller has said about the reg being limited is a crock of bleep e. (am I allowed to say bleep e. If not just remove the e)

If you don't care to read the other thread. The solution was to re-wire the panels in series. Then using a 12/24 volt MPPT to regulate the charge.

It has been about a week or a bit more. All is good. The battery has gone to float ( I have taken the Engel out of freeze mode ). With the Engel running at setting 1.5 and the laptop on charge all day, I am reading 13.8 to 14.3 volts at the battery with solar connected.

First thing in the morning I am reading 12.6 volts at the battery. By 10am the battery is back to float.

I can see from the photos in the eBay listing you gave, that the cell pattern of your panel is the same as mine!
AnswerID: 543089

Follow Up By: Chris85 - Wednesday, Dec 17, 2014 at 17:53

Wednesday, Dec 17, 2014 at 17:53
Thanks mate, good read on that post. I'm going to try and get a refund and then in going to low energy developments to buy a new setup. Have bought from them before, a tad more expensive but top product.
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FollowupID: 829968

Follow Up By: Kelpie D - Wednesday, Dec 17, 2014 at 18:53

Wednesday, Dec 17, 2014 at 18:53
No worries...

At least we all learnt we cannot say bleep even if you do add the e. In fact I bet you can't say bleep or bleep or even bleep. I bet you can't even say I would like to bleep you some day, unless your a doctor with a very large bleep...
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FollowupID: 829973

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