New to Solar, need help with my set up.

[70oldsracer]

I was given a solar panel from a friend of mine with no label, so I don’t have any specifications. I’m using the panel on my hunting blind, so my set up it’s not a critical one. I just want to be able to charge my phone, power a fan, cell phone booster and and few 12 volt lights. I really just need it to keep my battery charged while I’m not there. That being said, I bought a cheap 60 amp solar charge controller that can handle 100 volts, because my solar panel puts out around 40 volts in direct sunlight. I connected everything this weekend and at first, it seemed to be working fine. Then the LCD screen was showing full panel voltage. I’m not sure if this is normal or is there something wrong with the controller or the panel. I’m using a 12 volt AGM battery. I’m posting a video of the controller when I first hooked it up and another one after it was connected for a while. Any help would be greatly appreciated. Thanks

 

[snoobler]

Welcome to the forum.

PWM controllers work by shorting the panel to the battery. This is most appropriate for panel matched to batteries. Your 40V panel likely performs optimally around 30V. You're forcing it down to ~14V meaning whatever the panel's actual power is, you're cutting it in half due to forcing it to run at 1/2 the voltage. If this was a 250W panel, you would never see more than about 120W out of it due to the way PWM works.

When the battery reaches absorption voltage, the unit begins connecting and disconnecting it from the battery hundreds or thousands of times a second to maintain the absorption voltage. I would expect you might see full panel voltage when it's in that mode.

If you're seeing panel voltage closer to battery when the battery voltage is lower like in the first video, and it only shows high panel voltage when the battery is at higher voltage, I think everything is fine beyond the mismatch between the 12V battery and a non-12V panel.

Make sure your connections are all tight.

 

[Substrate]

Looks fine like the battery is already charged and operating normally.

But just to check - what is the capacity size of your agm? Just wondering in case the rapid rise that freaked you out is due to a very tiny agm like 9ah or so. Or maybe something highly sulfated.

Just checking...

 

[70oldsracer]

It's an Optima blue top marine battery D31M 75AH

 

[70oldsracer]

Can you recommend a good MPPT controller that’s not going to break the bank. I’d like to optimize my system, but agin, it’s for a hunting blind, so it’s more of a matter of luxury, not necessity. Thanks.

 

[70oldsracer]

Amazon.com : 40Amp MPPT Solar Controller 100V Input Tracker for Lithium Iron Phosphate LiFePO4 (Lead Acid AGM) Charger, Solar Panel Maximum Input 520W/1040W (12V/24V) Automatic (K40A) : Garden & Outdoor

Amazon.com : 40Amp MPPT Solar Controller 100V Input Tracker for Lithium Iron Phosphate LiFePO4 (Lead Acid AGM) Charger, Solar Panel Maximum Input 520W/1040W (12V/24V) Automatic (K40A) : Garden & Outdoor

www.amazon.com

Do you think this would work?

 

[Bob142]

For your consideration: a 20A Epever MPPT for $63.

20A 10A Epever MPPT Solar Charge Controller 12V/24V Battery Regulator Max PV 60V | eBay

Battery Temperature Sensor Epever Monitor Adapter RS485/USB Communication Cable. when the internal temperature reach 81â, the power reduction mode will be turned on. MPPT 1000W Grid Tie Inverter For 18V/36cells Solar Panel AC110V SolarEpic Power.

www.ebay.com

Many forum members have used similar model Epevers and appear to be satisfied. Last year someone had a similar situation and use case as you. They used this charge controller and it worked out well.

looking for charge controller for a 275 watt, 31v, rated current 8.9amps solar panel. I want to charge a 12v battery for my boat.

I was given a 275 watt, 31v, rated current 8.9amps solar panel. I want to charge a 12v battery for my boat. I'm a complete novice at solar. Previously there was a smaller solar module connected to a charge controller that matched it. .I'm hoping to find a charge controller to charge a 12v 100ah...

diysolarforum.com

 

[70oldsracer]

For your consideration: a 20A Epever MPPT for $63.

20A 10A Epever MPPT Solar Charge Controller 12V/24V Battery Regulator Max PV 60V | eBay

Battery Temperature Sensor Epever Monitor Adapter RS485/USB Communication Cable. when the internal temperature reach 81â, the power reduction mode will be turned on. MPPT 1000W Grid Tie Inverter For 18V/36cells Solar Panel AC110V SolarEpic Power.

www.ebay.com

Many forum members have used similar model Epevers and appear to be satisfied. Last year someone had a similar situation and use case as you. They used this charge controller and it worked out well.

looking for charge controller for a 275 watt, 31v, rated current 8.9amps solar panel. I want to charge a 12v battery for my boat.

I was given a 275 watt, 31v, rated current 8.9amps solar panel. I want to charge a 12v battery for my boat. I'm a complete novice at solar. Previously there was a smaller solar module connected to a charge controller that matched it. .I'm hoping to find a charge controller to charge a 12v 100ah...

diysolarforum.com

Thanks Bob, that looks like it should work perfect and within my budget. I’ll order it today and give and update once I have it all set up and running.

 

[70oldsracer]

I just ordered it, will it work with an AGM battery? Please say yes lol!!

 

[Bob142]

YES!

 

[70oldsracer]

Great, thanks for everything Bob

 

[70oldsracer]

So I purchased the charge controller you recommended. I just have two questions.
1) It doesn’t look like the panel is putting out any amps, see video.
2) The load connection on the controller seems to be putting out the same voltage as the battery when it’s being charged. I tested it with my volt meter and it was like 14.5. Is this going to be an issue when I try to run 12v lights or other 12 volt items.

 

[Short_Shot]

If there's no load and the battery is charged it won't do anything but sit there.

Try putting a load on the battery and see if it comes up. Turn on everything you've got and see what she says.

 

[70oldsracer]

Thanks, I’ll give that a try.

 

[Short_Shot]

Thanks, I’ll give that a try.

Report results

 

[70oldsracer]

I definitely will. It may take a while, because this setup is on my hunting blind which is 4 hours away. Next time I go up I’ll see and report back, thanks again.

 

[70oldsracer]

So I apologize for not updating this. Everything has been working great. I have a surveillance camera which is on 24/7 and it draws 8 watts. I’m also using a ubiquity Nano station 5 which I believe draws about the same, but let’s say they both draw 10 watts each for a total of 20 watts. I have a 100 watt solar panel and the solar charge controller mentioned in the earlier post. It rained Sunday through Monday and I lost power to the camera. I was up there on Sunday and everything was working. I finally got sun today and the camera is up and running. I have two optima blue top marine batteries which are 55ah each. Just wondering if anyone has an idea what the issue may be. Thanks in advance.

 

[70oldsracer]

This is the battery set up

 

[70oldsracer]

Also, I have a 750 watt inverter and that powers the ubiquity, the camera runs on 12 volts directly from the battery

 

[DThames]

100w panel, you will do good to get 80 watts for 4 hours a day, that is without any shade. Shade kills. So you might have 300-400 watt hours of charging per day, if you have good sun. If you have 20 watt load, 24/7, that is almost 500 watt hours. I suggest reduce your load or get more panels.

If your network device is powered from a wall charger, see if the charger's output is 12v. if so, you might power it from the battery and cut out the inverter. The inverter will use some power just being on.