Battery Not Charging From Solar

[matrixdutch]

Hey all!  I'm on the road right now, and my 250 amp hour deep cycle battery stopped charging.  After letting the system rest for 3 hours, it's been reading 11.5 volts on my meter for the last three days with good sun. I'm getting about 4.5 amps going to the battery, and the two 100 watt panels seem to be taking in about 16 watts.  I also have a 40 amp mppt controller connected.

I'm not sure if my battery is shot.  What equipment and steps do I need to take to troubleshoot the problem?

 

[jimindenver]

Check for good connections. Check and see if the battery needs distilled water, are the panels clean?

What is your controller ans battery?

 

[BradKW]

Not sure where you're testing, but if just going by what the mppt CC is saying, you should check at the battery terminals too...both to make sure the power is arriving, and that corrosion isn't preventing a good contact.

 

[matrixdutch]

Check for good connections. Check and see if the battery needs distilled water, are the panels clean?

What is your controller ans battery?

I have a renogy 40 amp mppt controller, and a UPG 12V 250AH AGM Sealed Lead-Acid Battery.

The connections seem clean, and I've cleaned the panels every morning.

 

[matrixdutch]

Not sure where you're testing, but if just going by what the mppt CC is saying, you should check at the battery terminals too...both to make sure the power is arriving, and that corrosion isn't preventing a good contact.

How do I do that?

 

[matrixdutch]

Also, when it's charging, the meter shows it float to as high as 12.1 volts

 

[GotSmart]

Buy a inexpensive electrical tester, and check out what the readings are at in different spots.

You could have received a bad controller. If so, Renogy will immediately respond to a phone call.

 

[jimindenver]

Float at 12.1v is not right.

 

[GotSmart]

Float at 12.1v is not right.

My first thought is miscalibrated controller, second is a bad battery. 

The wires should not cause a 12% drop in readings.

 

[jimindenver]

That's a huge battery, I know I have 3 that size. First thing is do you have any other means of charging? You really need to get that battery up and as soon as possible. Also remove any loads so that it isn't drained further. Even fully functional that 200w has a lot of work to do before that battery is back up to a full charge. I'd guess at least 3 days with no loads.

How old is the set up?

 

[matrixdutch]

Buy a inexpensive electrical tester, and check out what the readings are at in different spots.

You could have received a bad controller. If so, Renogy will immediately respond to a phone call.

I don't know how to use a tester, but I will Google.

I will also reach out to Renogy.

Thanks

 

[highdesertranger]

are you checking the 11.5 at the battery with a meter? how long have you had this system? was it ever working right? when you hooked it up did you connect the battery first? have you ever disconnected the battery while the panels where delivering power to the controller? highdesertranger

 

[matrixdutch]

That's a huge battery, I know I have 3 that size. First thing is do you have any other means of charging? You really need to get that battery up and as soon as possible. Also remove any loads so that it isn't drained further. Even fully functional that 200w has a lot of work to do before that battery is back up to a full charge. I'd guess at least 3 days with no loads.

How old is the set up?

Unfortunately I don't have another way to charge it like a solenoid.

The setup is about 6 months old

 

[matrixdutch]

are you checking the 11.5 at the battery with a meter?  how long have you had this system?  was it ever working right?  when you hooked it up did you connect the battery first?  have you ever disconnected the battery while the panels where delivering power to the controller?  highdesertranger

I don't know how to test with a meter at this time, but I will research how to do it so I can see.

It has been working fine since last week.

I don't recall whether I hooked the battery up first... I did follow the order provided in the manuals.  I've also never disconnected the battery while the panels were delivering power to the controller.

Thanks

 

[jimindenver]

How heavy are the wires from the controller to the battery? This wire can cause loss of voltage between them as well as make it so the controller can't read the batteries voltage.

I want to suggest disconnecting first the panels and then the battery. Let it sit for 5 minutes and reconnect the battery first and then the panels. See if a reboot doesn't help things.

For a lower power user a 8-D holds a huge amount of power and could have taken a long time to get down from a full charge to this point.

One more question. How are the panels wired? In series will give the MPPT more voltage to work with than in parallel. Series means the two panels are connected together with the remaining positive and negative leads going to the controller.

 

[matrixdutch]

How heavy are the wires from the controller to the battery? This wire can cause loss of voltage between them as well as make it so the controller can't read the batteries voltage.

I want to suggest disconnecting first the panels and then the battery. Let it sit for 5 minutes and reconnect the battery first and then the panels. See if a reboot doesn't help things.

For a lower power user a 8-D holds a huge amount of power and could have taken a long time to get down from a full charge to this point.

One more question. How are the panels wired? In series will give the MPPT more voltage to work with than in parallel. Series means the two panels are connected together with the remaining positive and negative leads going to the controller.

The wires are 10awg.

I have the panels wired in parallel.

I will take the steps you recommended and see what happens.

Thanks

 

[GotSmart]

Unfortunately I don't have another way to charge it like a solenoid.

The setup is about 6 months old

Simple to wire in.

https://www.amazon.com/gp/product/B008R1T5IM/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1

Incoming wire from Alternator to fuse.  Top wire hot FROM fuse. There are 4 gauge wires that have the ends pressed on with a hydraulic crimper.

Second wire to 5A switch on dashboard powered from the running ignition system. ( If the van is not turned on, the switch will not operate.)

Third wire to ground on frame

Bottom wire to battery.

NOTE THE POSITIONING OF THE SWITCH!

 

[jimindenver]

You mentioned it was fine a week ago. May I ask what voltages you were seeing? Float voltage should be in the 13's and charging in the 14's.

 

[matrixdutch]

Simple to wire in.

https://www.amazon.com/gp/product/B008R1T5IM/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1

Incoming wire from Alternator to fuse.  Top wire hot FROM fuse.  There are 4 gauge wires that have the ends pressed on with a hydraulic crimper.

Second wire to 5A switch on dashboard powered from the running ignition system. ( If the van is not turned on, the switch will not operate.)

Third wire to ground on frame

Bottom wire to battery.

NOTE THE POSITIONING OF THE SWITCH!

Interesting, I'll look this over.

Thanks

 

[matrixdutch]

You mentioned it was fine a week ago. May I ask what voltages you were seeing?  Float voltage should be in the 13's and charging in the 14's.

Yes, it used to float around 13 & 14 when the battery was close to being full, or full.  

I unplugged the panels and the battery, then reconnected.  Still the same.  Panels read 16.3 volts coming in.  Battery charging at 3.5 volts, and reading at 11.8 v