System has some issues

[Hedges]

I'm starting to be convinced everything is working perfectly. Negative numbers means charging, not discharging?
Try plugging a load into the inverter, maybe a 600W space heater. Then see what the display says.
That may confirm all is good.

Do that with engine off, so results aren't confused by any change in what comes from alternator.
OK to try it with engine on as well, see if anything different.

 

[Bribenn]

Hmm. I don't have a space heater, but I plugged in a drill. Here's what it says...

 

[Hedges]

12.11V -58W

Not a big enough change from the others to be conclusive. Have a hair dryer? That would be hundreds or 1000W. Coffee pot?

I note the voltage is even lower now.

Is this a lithium battery?
12.11V would be fairly low for lead-acid, except under load.
Lithium doesn't change voltage much with state of charge (in the middle of its range), but I expect voltage to drop during discharge, increase during charge.

 

[Bribenn]

12.11V -58W

Not a big enough change from the others to be conclusive. Have a hair dryer? That would be hundreds or 1000W. Coffee pot?

I note the voltage is even lower now.

Is this a lithium battery?
12.11V would be fairly low for lead-acid, except under load.
Lithium doesn't change voltage much with state of charge (in the middle of its range), but I expect voltage to drop during discharge, increase during charge.

It's a lead acid battery. I got an alarm yesterday on my inverter that signaled low voltage. Before that, everything was working pretty well. Not sure what changed. I did use maybe a lot of power with a space heater the day before. Which I don't have with me now. Looking for something with more watts to plug in.

 

[Bribenn]

It's a lead acid battery. I got an alarm yesterday on my inverter that signaled low voltage. Before that, everything was working pretty well. Not sure what changed. I did use maybe a lot of power with a space heater the day before. Which I don't have with me now. Looking for something with more watts to plug in.

It's a lead acid battery. I got an alarm yesterday on my inverter that signaled low voltage. Before that, everything was working pretty well. Not sure what changed. I did use maybe a lot of power with a space heater the day before. Which I don't have with me now. Looking for something with more watts to plug in.

Ok, ran a 620 watt drill and here's what it said.

 

[Hedges]

11.92V -238W

Still not a large load (not enough to swamp out that -400W reading), but still negative watts and lower voltage.
So it does appear that negative watts means discharge.

Lead acid battery at 12.1V is low. Have a battery charger? It should be recharged to a decent state of charge before it becomes degraded.
Is that FLA wet cell? AGM? Gel?
For my AGM batteries, 12.1V is about 50% charge (with light load or no load)

It does seem like you are correct, that house battery is being drained while car is running, same polarity negative watts shown as when you run a load. That isn't expected, would think charger would only pull from car's electrical system to charge it, not discharge it.

Do you have a handheld voltmeter? Can you check voltage on alternator and starter battery?

In its most basic usage, this charge controller ought to take power from your PV panels and charge the battery, with no inverter or alternator connected.
I see "input", and under that only "starter battery" is shown. Any other items available by scrolling the display?
Have a schematic, maybe a link to the manual?

 

[Bribenn]

11.92V -238W

Still not a large load (not enough to swamp out that -400W reading), but still negative watts and lower voltage.
So it does appear that negative watts means discharge.

Lead acid battery at 12.1V is low. Have a battery charger? It should be recharged to a decent state of charge before it becomes degraded.
Is that FLA wet cell? AGM? Gel?
For my AGM batteries, 12.1V is about 50% charge (with light load or no load)

It does seem like you are correct, that house battery is being drained while car is running, same polarity negative watts shown as when you run a load. That isn't expected, would think charger would only pull from car's electrical system to charge it, not discharge it.

Do you have a handheld voltmeter? Can you check voltage on alternator and starter battery?

In its most basic usage, this charge controller ought to take power from your PV panels and charge the battery, with no inverter or alternator connected.
I see "input", and under that only "starter battery" is shown. Any other items available by scrolling the display?
Have a schematic, maybe a link to the manual?

I have AGM batteries.
The starter battery reads at like 7, but I think this reader is broken.
Nothing else at the bottom of the display except relay state open.

Can I charge the batteries while everything is hooked up?

 

[Bribenn]

I can't send a link because I'm on my phone at a garage and I barely have service. But you can find the manual by googling like this.

 

[Hedges]

Sure, you should be able to attach a charger. Have one intended for AGM? Be sure not to charge above data sheet recommendation of voltage. Doesn't sound like you have a handheld DMM? It helps to have a meter when working with batteries, even if a cheap one from Harbor Freight.

Strange that your charge controller doesn't even show "PV panels" or "Alternator".

Looks like your charge controller is this:

DCC50S 12V 50A DC-DC On-Board Battery Charger with MPPT

Make sure your service battery has all the juice it needs with Renogy's DCC50S DC-DC MPPT On-Board Battery Charger. 10% off: Renogy10off. Free shipping

www.renogy.com

Is this your Victron BMV:

Victron Energy BAM010702000R Battery Monitor BMV-702

Victron Energy Battery Monitor BMV-702 Black will display Battery voltage, current, power, ampere-hours consumed and state of charge and so much more.

invertersrus.com

I'm not clear on which gives you the display. Neither has a display the size you show, but it looks like screen of a phone that linked to the device.

If you have a DMM, you can check open-circuit voltage of panels, see if voltage drops to about Vmp when connected and should be providing power. You should see a voltage for the battery resting, and higher voltage when charging. Lower voltage when discharging.

 

[Bribenn]

Sure, you should be able to attach a charger. Have one intended for AGM? Be sure not to charge above data sheet recommendation of voltage. Doesn't sound like you have a handheld DMM? It helps to have a meter when working with batteries, even if a cheap one from Harbor Freight.

Strange that your charge controller doesn't even show "PV panels" or "Alternator".

Looks like your charge controller is this:

DCC50S 12V 50A DC-DC On-Board Battery Charger with MPPT

Make sure your service battery has all the juice it needs with Renogy's DCC50S DC-DC MPPT On-Board Battery Charger. 10% off: Renogy10off. Free shipping

www.renogy.com

Is this your Victron BMV:

Victron Energy BAM010702000R Battery Monitor BMV-702

Victron Energy Battery Monitor BMV-702 Black will display Battery voltage, current, power, ampere-hours consumed and state of charge and so much more.

invertersrus.com

I'm not clear on which gives you the display. Neither has a display the size you show, but it looks like screen of a phone that linked to the device.

If you have a DMM, you can check open-circuit voltage of panels, see if voltage drops to about Vmp when connected and should be providing power. You should see a voltage for the battery resting, and higher voltage when charging. Lower voltage when discharging.

Yeah, that's the charge controller. It has lights that say what is happening. Like solar charging, battery state, and alternator charging.

I have a multimeter, but like I said, I think it's. Token because it's saying 7 for my car battery.

I have the victron 712 smart.

 

[Bob142]

@Bribenn: Do you still have that extra negative wire going from the busbar to the battery? If so, please remove it.


@Hedges: Diagram and photos of the system are in a different thread:

Kill switch doesn't turn off all power

Hi, I recently set up a solar system in my van and it is all working well except for one small (potentially huge) thing. I have a kill switch wired directly off of the battery with the intention to be able to quickly shut off power should anything go wrong. When I turn it to the off position...

diysolarforum.com

 

[Bribenn]

No, I removed it.

 

[Bribenn]

Sure, you should be able to attach a charger. Have one intended for AGM? Be sure not to charge above data sheet recommendation of voltage. Doesn't sound like you have a handheld DMM? It helps to have a meter when working with batteries, even if a cheap one from Harbor Freight.

Strange that your charge controller doesn't even show "PV panels" or "Alternator".

Looks like your charge controller is this:

DCC50S 12V 50A DC-DC On-Board Battery Charger with MPPT

Make sure your service battery has all the juice it needs with Renogy's DCC50S DC-DC MPPT On-Board Battery Charger. 10% off: Renogy10off. Free shipping

www.renogy.com

Is this your Victron BMV:

Victron Energy BAM010702000R Battery Monitor BMV-702

Victron Energy Battery Monitor BMV-702 Black will display Battery voltage, current, power, ampere-hours consumed and state of charge and so much more.

invertersrus.com

I'm not clear on which gives you the display. Neither has a display the size you show, but it looks like screen of a phone that linked to the device.

If you have a DMM, you can check open-circuit voltage of panels, see if voltage drops to about Vmp when connected and should be providing power. You should see a voltage for the battery resting, and higher voltage when charging. Lower voltage when discharging.

Currently charging with a slow charge at 6amps. I don't understand why the voltage is so low, but everything says the battery is full.

 

[Hedges]

Currently charging with a slow charge at 6amps. I don't understand why the voltage is so low, but everything says the battery is full.

The monitor probably doesn't know full from empty, hasn't learned or been set to 100%.
Since battery is AGM, just charge to appropriate voltage (adjusted for temperature if necessary) according to battery spec.
Proper charge probably requires holding at constant voltage toward the end for some number of hours. If your charger isn't going to do that, disconnect rather than driving voltage too high.

 

[Bribenn]

The monitor probably doesn't know full from empty, hasn't learned or been set to 100%.
Since battery is AGM, just charge to appropriate voltage (adjusted for temperature if necessary) according to battery spec.
Proper charge probably requires holding at constant voltage toward the end for some number of hours. If your charger isn't going to do that, disconnect rather than driving voltage too high.

Alternatively, I can plug in to shore power with my inverter. That will be fine, right?

 

[Hedges]

Alternatively, I can plug in to shore power with my inverter. That will be fine, right?

Sure, if that has a charger which works. Is it set for your AGM parameters, knows how to charge it properly?

Of course, you will need some state of partial discharge to debug the other charging units. But I was concerned 12.1V was going to damage battery after a period of time.

 

[Bribenn]

Sure, if that has a charger which works. Is it set for your AGM parameters, knows how to charge it properly?

Of course, you will need some state of partial discharge to debug the other charging units. But I was concerned 12.1V was going to damage battery after a period of time.

How long at 11.7 volts until my batteries are damaged? Perhaps they are already damaged. I can't imagine how it's gotten to that low of volts, honestly.

 

[Hedges]

11.7V is 60% to 80% DoD while discharging, or 90% DoD at rest, from the technical manual for my SunXtender.
It is OK to draw them down to that, just not sure how quickly damage occurs. I wouldn't think in one day, since they are meant to be cycled.

 

[Bribenn]

11.7V is 60% to 80% DoD while discharging, or 90% DoD at rest, from the technical manual for my SunXtender.
It is OK to draw them down to that, just not sure how quickly damage occurs. I wouldn't think in one day, since they are meant to be cycled.

? Good because I can't charge them tonight. I'll try again in the morning. Hopefully can get this figured out before my trip Thursday morning.

 

[Bribenn]

My batteries are at 11.8v according to dmm. I'm trying to see if my solar panels will charge the batteries since it's a really sunny day today. I checked the voltage coming in from my solar panels and it's 18v from the solar cable into the charge controller. Is that normal? There are 3 100 watt 12v panels. They are connected in parallel, all 3 positives into one branch connector and same with negatives.