Offgrid Over Voltage issue. Over Voltage light blinking on PWM

WastelanderGuy · July 2016

Greetings!
When I plug my solar panel into to my PWM, it says that it is "Over Voltage" (Blinking green light, whereas solid green would mean "Charging"). Sadly the PWM's manual doesn't give much in the way of a description and I am at a bit of a loss as to what this means.
Heck, I was worried my solar panel was going to be too small.
Is this just merely an issue of the PWM being to puny, and should I bump up to a 30A PWM, or am I missing something completely?
This is my first build and I thought I had done all my research, crossed my T's, dotted my I's, etc. and that it should be working pretty spot-on.

Thanks for any input on this. Totally scratching my head over here.

Here's what I'm working with:
PWM ~
20A cheapo from China
specs: http://www.ebay.com/itm/111988614245?_trksid=p2057872.m2749.l2649&var=410930968477&ssPageName=STRK:MEBIDX:IT

Solar Panel ~
Specs summary: 100W Polycrystalline Solar Panel; Peak Power:100W; Max Power Voltage(Vmp):18V; Max Power Current(Imp):5.56A; Open Circuit Voltage(Voc):21.6V; Short Circuit Currect(Isc):5.95A; Max System Voltage:600V
full specs: http://www.ebay.com/itm/182197628255?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

Battery ~
1x 100ah Marine Deep Cycle

westbranch · July 2016

you did not tell us what the conditions such as temp are today where ever you are...??

Barring that, if you plans on getting more panels, I think you need a a MidNite BRAT... http://www.midnitesolar.com/pdfs/spec_sheet_brat_frontBack.pdf
thjat cheap Chinese charge controller may be DOA...

BB. · July 2016

One other possibility, make sure you connect the charge controller to the battery bank first, then connect the solar panels next.

Depending on the controller, some will get "confused" if the solar array (under sun) is connected first and the battery bank second.

-Bill

WastelanderGuy · July 2016

Westbranch: It was pretty gnarly hot. I think 106°+ in the sun. Batteries were in the shade, which was probably around 100°. Technically, this setup will be for camping in the desert (No, not Burningman) and will be in similar conditions.

BB: Yes, the batteries were connected first. Lol, yeah that Chinese PWM might be a dud.

WastelanderGuy · July 2016

Also, that Midnite Brat is nice, but $$$.

westbranch · July 2016

And like Aspirin,.... it works from the start, day in and day out.... I have a small 10A No-name cc and it is good for the single battery that needs to be charged for random use in the camper, but the Brat was not out there at that time... if only it was, that is what I would have used, or maybe one of the Morningstars......

Johann · July 2016

How many solar panels do you have?
Are they wired in parallel or in series if you have more than one panel?

I am interested how you wired the system together because it sounds like that you may have a problem/mistake the way you wired it.
Could you post a wiring diagram how you wired it? A sketch on paper would be fine as long as we can make it out.

To note here is,... that many cheaper controller using the plus + as the common internally and NOT THE MINUS.of the charge controller . If you hook all or some of your minus - wires together, you just jumped and bypass the controllers control circuit and the controller can not regulate the incoming power anymore and will supply the full power to the batteries when the sun is out.
Solar panel minus need to go to the solar panel minus terminal at the CC, the minus for the battery need to go to the minus terminal at the CC and the same with load wires and load terminals........Do not connect any of those minus wires together or the charge controller may not be able to regulate it and will overcharge your batteries. Also be careful how and where you wire your ground/ ground wire into the system if it is incorporated.

I have cheap 30 amp controllers, since my MPPT burned up 2 month after the warranty was up. Well over a 100 F today no problem, I have my batteries 350Ahr outside also. I also have the renogy 100DG panels. Made 1972 ahr per my $30 cheap controller readout on it so far on the older controller that I am testing. I just hooked up a new same second controller yesterday.

WastelanderGuy · July 2016

Thanks for the responses, guys!

The setup is pretty straight forward:
A single panel going into the solar + and - of the PWM, a single battery going the battery + and - of the PWM, and load going to load of the = and - of the PWM

Johann · July 2016

WastelanderGuy said:

Thanks for the responses, guys!

The setup is pretty straight forward:
A single panel going into the solar + and - of the PWM, a single battery going the battery + and - of the PWM, and load going to load of the = and - of the PWM

Nothing wrong here. Thank you for posting the diagram/wiring schematic.

Johann · July 2016

Which light is blinking?
The first indicator light to the left?
Or the 2nd indicator light in the middle?

If the first indicator light ( left light) is blinking green, that means over voltage.
If second indicator ( middle) is blinking green, that means that the battery is fully charged.

WastelanderGuy · July 2016

Johann: It's the first indicator to the left. So yes, it's saying it's in overvoltage.

Cuprs · July 2017

Hi I know this post is a year old! but

Just wondering if you got to the bottom of this issue? I have the same setup as you (Same controller) and im getting the same issue?

Cheers

littleharbor2 · July 2017

First off, Welcome to the forum. OK now tell us about your panels, brand/model, specs, wiring configuration, battery.
Overvoltage says to me, panels wired in series or wrong voltage panel as opposed to parallel, or faulty controller.

Cuprs · July 2017

Hi thanks for the reply, Im very new to this and its my first attempt

This is the Panel and controller I have got

http://www.ebay.co.uk/itm/20w-Light-Weight-Solar-Panel-10A-12v-24v-Battery-Charger-Controller-4m-cable-/261912374098

I haven't got the battery information on me but its an old unused UPS 12v bat I had available.

The plan is to power a small led light strip powered for about an hour a day and activate a small door mech twice a day for a chicken coop on a 12v timer.

Thanks again

littleharbor2 · July 2017

And is the far left led rapidly blinking? Slowly blinking means fully charged.

Cuprs · July 2017

Yes the far left sun indicator is blinking rapidly green and the batt indicator is solid red.
Cheers

littleharbor2 · July 2017

Red battery indicator is a severely discharged battery. I would disassemble the whole setup. Find a way to charge and confirm your battery isn't in fact shot. Do you have a multimeter to test voltage? Charge controllers need to be connected to a good battery FIRST. They will chose the system voltage by the voltage of the battery. After connecting the battery then connect the solar. Be sure all polarity is correct.
Are you trying to run your load off the load output on the controller?.

Cuprs · July 2017

Thanks i assumed the batt was ok as it powers the lights etc but guess it could be very low as it been sitting around a long time. I can borrow a mulitimeter and check.
Yes the Small led strip is connected to the output of the controller.
Thanks again

littleharbor2 · July 2017

Voltage below 12 volts should be considered totally drained. Your battery May be shot from sitting around getting sulphated. If it appears to charge up very fast, that would be a red flag that it is no good and has no capacity left. Always best to start with a known good, freshly charged battery.

Cuprs · July 2017

Thanks mate I'll let you know how I get on..
Cheers

Cuprs · December 2017

Hi All,
Still some issues I’m afraid,
The system seem to be working ok for a while but now has stopped working.
I’ve replaced the batt,
What seems to happen is I get a flashing green solar indicator during the day but the battery indicator very rarely goes green.
This morning when I looked at it my setup it had stopped working and my batt indicator is flashing red.
Could this be a faulty solar controller (it’s just a cheap Chinese one?)
(See setup above,I no longer have the strip light just the door mech, which is an old car Ariel motor, which had a load on it through the night to keep the door shut, once the motor has turned it doesn’t do anything until the morning when it’s unwound, opening the door)
One thing I didn’t note before is I use a timer to operate the load on / off

12V/24V/110V/220V LCD Digital Programmable Control Power Timer Switch Relay L701

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/122145625760

Any help appreciated
Cheers Ryan

Cuprs · December 2017

This unit stripped down is what I’m using for a motor

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/292208024177

mike95490 · December 2017

Got any voltage readings - even from a $8 DVM ? Green, red, blinking, I don't know the sequence info for your controller, what does your manual say it means ?

Estragon · December 2017

Also, what kind of replacement battery?

Cuprs · December 2017

Hi guys thanks for the reply
The rapid green flashing on the solar indicator says it’s an “over voltage”

The replacement battery is this

https://www.screwfix.com/p/sealed-lead-acid-battery-12v-7ah-100-x-65-x-151mm/38315#product_additional_details_container

When I measured the batt yesterday it was around 12.8v

Thanks again

Estragon · December 2017

Does the timer disconnect the battery from the controller as well as the motor? If the controller sees voltage from the panel with no battery, it could put the controller into a weird state and/or put high open circuit pv voltage to the controller with no battery to bring it down.

Also, not clear on the "motor had a load on it through the night" statement. Does it take power to keep the door closed, or just to close the door?

12.8v is about right for a fully charged battery with no loads or charging source. Was it charging when you took the reading?

Offgrid Over Voltage issue. Over Voltage light blinking on PWM

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