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Dead 12V battery in spite of Solar

Ella

New member
We have just became the owners of 2023 Paradigm with a solar panel already installed on the roof. The dealer also put in 2 acid 12V batteries and as we were explained the key function of the solar panel is to charge 12V battery.
Got home, parked the rig, two days later there is 0 juice in 12V. Looked at the fuse panel insides the coach - nothing is tripped. In the generator compartment all the wires seem to be connected (no loose wires).

Also probably worth mentioning, during the PDI, the batteries were not charged when the tech opened the generator compartment, which I thought was strange as they are the dealer supposed to fill/charge everything up, but, possibly due to our lack of experience, we didn’t make a big deal out of this. The tech connected the coach to the shore line and battery got fully charged.
This morning got in touch with the dealer - Tacoma RV; they said someone will contact us from the Service department on Monday, which is frustrating since we have a trip planned.

While waiting on the service guys to call in, would really appreciate if someone will give me some clues of what could be causing this (faulty battery?, bad connection to solar?, bad solar panel?, etc). Also any advice on handling service calls would be appreciated as well. This is our first RV and we were so excited to finally pick one up! Now it’s just sitting there dead in the water.
 
I would need more info to more accurately guide you. how many watts of solar on the roof? Residential fridge? Are your batteries going flat while plugged in?

the residential fridge can be a power of particularly if it’s neat empty as it will be running through an inverter and losing at least 20% efficiency by doing so. Your batteries may have also suffered permanent damage and may not hold a charge, I would insist on having them replaced.

what does the display on your solar charger indicated?
 

bhidalgo

Well-known member
Ella,

Congratulations on the new Paradigm. We’re coming up on a year of ownership and really do enjoy ours.

Get rid of the batteries you have and get Lithium Ion - Just my suggestion. You can run them all the way down to just about 0V and do little to no damage to them, and they will still charge back up to full charge capacity.

We have been having similar issues with our 310RL that you are having. My guess is that when you discovered the problem you are having your Inverter was flashing an E-1 error, and your battery charge was less than 12v. The problem is capacity - your solar panel combined with the batteries is not enough to keep the refrigerator powered for more than a couple of days. When you add the draw from the Frig, the inverter, and your solar controller/battery charger, the solar panel cannot provide enough juice to keep the batteries sufficiently charged. We have 2 Renogy 100AH batteries and a 320W solar panel, along with a Renogy 60MTT solar controller / battery charger, and a 2KW inverter. I spoke to Alliance Service yesterday and they told me I need to add another battery along with another panel of the same capacity to provide the added capacity we need to keep our refrigerator running for a few days, along with minimal power usage in the rig. We’re looking at about $2300 to upgrade our current solar system.

Call Alliance Service and ask to speak to a Solar expert to get info specific to your rig.

Good luck…Bill
 

Kbayshaper

New member
Same issue here. Just picked up my 382RK and after getting it home and into storage, I notice the charge controller is showing night mode and not charging the battery (daytime). I checked the wires into the controller and noticed the negative from the panel was loose. I retightened it but it was still not charging the battery mid day. Battery later drained down to nothing. It's currently at the shop awaiting diagnosis.
 
Ella,

Congratulations on the new Paradigm. We’re coming up on a year of ownership and really do enjoy ours.

Get rid of the batteries you have and get Lithium Ion - Just my suggestion. You can run them all the way down to just about 0V and do little to no damage to them, and they will still charge back up to full charge capacity.

We have been having similar issues with our 310RL that you are having. My guess is that when you discovered the problem you are having your Inverter was flashing an E-1 error, and your battery charge was less than 12v. The problem is capacity - your solar panel combined with the batteries is not enough to keep the refrigerator powered for more than a couple of days. When you add the draw from the Frig, the inverter, and your solar controller/battery charger, the solar panel cannot provide enough juice to keep the batteries sufficiently charged. We have 2 Renogy 100AH batteries and a 320W solar panel, along with a Renogy 60MTT solar controller / battery charger, and a 2KW inverter. I spoke to Alliance Service yesterday and they told me I need to add another battery along with another panel of the same capacity to provide the added capacity we need to keep our refrigerator running for a few days, along with minimal power usage in the rig. We’re looking at about $2300 to upgrade our current solar system.

Call Alliance Service and ask to speak to a Solar expert to get info specific to your rig.

Good luck…Bill
Bill I have what I believe is 320 watt solar in 2 panels with a 20 AMP controller on a 32RLS. I guess I got most of the OTG package but not all because I did not get the 2000 watt inverter.

My question is how is a 20 amp controller enough for 320 amps of solar? 320/12 is 26.6 amps. Clearly a 20 amp controller is inadequate.

I wonder if I really have 320 watts in the 2 panels or is it actually less - thus a 20 amp controller - or is the controller undersized?

Oh and I have a dead fridge by morning with 2 x 100ah lead acid batteries charged to 100% by the evening and minimal other 12v use. I'm talking CO detector chirping at 6:00 dead. My wife and dog love that.

Needless to say, I have 2 x 100ah Renogy Lithium batteries are on the way now via ups which has me cautiously optimistic.

We'll see how that goes but I figure (even with lithium) I either need more panels on the roof and a bigger controller or a bigger controller for the 2 I have now.

My RV buddies all have fridges that run on propane as a back up. My only explanation to them is that my camper is simply more woke than theirs - and for that I am teased relentlessly. 12v only fridges like ours, even when they're handsome and big, are a PITA. An undersized solar system to offset the lack of an alternate power source is not a solution. It's more of a tease actually and a bit of a bomb in the lap of unknowing buyers - IMHO. Me among them.

Do your homework and get your wallet out if you want the fridge to keep you stuff cold when you're dry camping. It comes down to a lot more solar and/or a generator. I say "and" because the sun doesn't always shine.

I have the generator and am working on the solar.
 

Oregon_Camper

Forum Moderator
Staff member
Bill I have what I believe is 320 watt solar in 2 panels with a 20 AMP controller on a 32RLS. I guess I got most of the OTG package but not all because I did not get the 2000 watt inverter.

My question is how is a 20 amp controller enough for 320 amps of solar? 320/12 is 26.6 amps. Clearly a 20 amp controller is inadequate.

I wonder if I really have 320 watts in the 2 panels or is it actually less - thus a 20 amp controller - or is the controller undersized?

Oh and I have a dead fridge by morning with 2 x 100ah lead acid batteries charged to 100% by the evening and minimal other 12v use. I'm talking CO detector chirping at 6:00 dead. My wife and dog love that.

Needless to say, I have 2 x 100ah Renogy Lithium batteries are on the way now via ups which has me cautiously optimistic.

We'll see how that goes but I figure (even with lithium) I either need more panels on the roof and a bigger controller or a bigger controller for the 2 I have now.

You need to do more research on how solar and MPPT controllers work. The 20amp you see on the Renogy MPPT controller is the amps it can output to the battery bank. Voltage is what powers the MPPT controller, not amps. That 20 amp controller is plenty for your 320 watt panel.

1696058562021.png


Your current AGM battery bank will only provide you 1/2 of stated amps. Your new Lithium will provide 100%. You will need to flip the switch on the converter to "LI" so it charges correctly. You should also buy a shunt for the new Lithium batteries, as Lithium batteries will hold their voltage just over 12.5 volts until they are about 14% remaining. Using the "battery level" LED gauge will NOT provide you proper power readings once you move to Lithium. As you can see in the chart below, Lithium will still be over 12.5 volts with only 14% remaining, yet your LED gauge will report that as full. Finally, put your frig into "night mode" when going to bed. That puts it into an 8 hrs sleep mode and uses hardly any amps. The idea behind this is everyone is asleep and the door won't be opening.

Chart below is for Lithium batteries
1696059139096.png
 
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You need to do more research on how solar and MPPT controllers work. The 20amp you see on the Renogy MPPT controller is the amps it can output to the battery bank. Voltage is what powers the MPPT controller, not amps. That 20 amp controller is plenty for your 320 watt panel.

View attachment 1373


Your current AGM battery bank will only provide you 1/2 of stated amps. Your new Lithium will provide 100%. You will need to flip the switch on the converter to "LI" so it charges correctly. You should also buy a shunt for the new Lithium batteries, as Lithium batteries will hold their voltage just over 12.5 volts until they are about 14% remaining. Using the "battery level" LED gauge will NOT provide you proper power readings once you move to Lithium. As you can see in the chart below, Lithium will still be over 12.5 volts with only 14% remaining, yet your LED gauge will report that as full. Finally, put your frig into "night mode" when going to bed. That puts it into an 8 hrs sleep mode and uses hardly any amps. The idea behind this is everyone is asleep and the door won't be opening.

Chart below is for Lithium batteries
View attachment 1374
Thanks for your help Jim! I did not know there was night mode on the fridge and I bet it'll make a big difference.

On the shunt, I am familiar, and see the value being with a smart one being able to monitor remotely. I have the bluetooth module on the RVR-20 and it gives me battery condition and other info. Do you think that will do an adequate job of providing lithium battery status or should I get the smart shunt too?

Also, in the chart with the Renogy model specs, I see that the RVR-20 (what I have) is rated for a max solar input power of 260w at 12v. My (battery) system is 12v. Am I missing something or would my 320w solar be too much for the controller? I know you said the RVR-20 is plenty, so I guess I'm still unclear. I've watched a couple YouTube videos on operating the unit and know that how the 2 panels are wired (in series or parallel) would impact the input voltage but my understanding is the 12 or 24 volt settings refer to the battery bank. Am I wrong about that?
 
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Oregon_Camper

Forum Moderator
Staff member
Thanks for your help Jim! I did not know there was night mode on the fridge and I bet it'll make a big difference.

On the shunt, I am familiar, and see the value being with a smart one being able to monitor remotely. I have the bluetooth module on the RVR-20 and it gives me battery condition and other info. Do you think that will do an adequate job of providing lithium battery status or should I get the smart shunt too?

Also, in the chart with the Renogy model specs, I see that the RVR-20 (what I have) is rated for a max solar input power of 260w at 12v. My (battery) system is 12v. Am I missing something or would my 320w solar be too much for the controller? I know you said the RVR-20 is plenty, so I guess I'm still unclear. I've watched a couple YouTube videos on operating the unit and know that how the 2 panels are wired (in series or parallel) would impact the input voltage but my understanding is the 12 or 24 volt settings refer to the battery bank. Am I wrong about that?

Get the Victron shunt....it will provide you with incoming and outgoing amps. It is the only true way to determine power levels. Plus you can monitor it from your phone :)

Your solar panel are way more than 12v...more like 24-30 volts per panel. You can either double the voltage or amps, depending on if you wire in series or parrallel.

Shown below is the reference of a 320 watt solar panel from Renogy. You can see the Vmp is 32.7. That is incoming voltage....then the controller uses the higher voltage and converts that to ~13 volts and variable amps (depending on sunlight on panels) on the outgoing side to charge the battery bank.

1696140131234.png
 
Get the Victron shunt....it will provide you with incoming and outgoing amps. It is the only true way to determine power levels. Plus you can monitor it from your phone :)

Your solar panel are way more than 12v...more like 24-30 volts per panel. You can either double the voltage or amps, depending on if you wire in series or parrallel.

Shown below is the reference of a 320 watt solar panel from Renogy. You can see the Vmp is 32.7. That is incoming voltage....then the controller uses the higher voltage and converts that to ~13 volts and variable amps (depending on sunlight on panels) on the outgoing side to charge the battery bank.

View attachment 1375
Thanks again Jim!
 

DanNJanice

Well-known member
Thanks for your help Jim! I did not know there was night mode on the fridge and I bet it'll make a big difference.

On the shunt, I am familiar, and see the value being with a smart one being able to monitor remotely. I have the bluetooth module on the RVR-20 and it gives me battery condition and other info. Do you think that will do an adequate job of providing lithium battery status or should I get the smart shunt too?

Also, in the chart with the Renogy model specs, I see that the RVR-20 (what I have) is rated for a max solar input power of 260w at 12v. My (battery) system is 12v. Am I missing something or would my 320w solar be too much for the controller? I know you said the RVR-20 is plenty, so I guess I'm still unclear. I've watched a couple YouTube videos on operating the unit and know that how the 2 panels are wired (in series or parallel) would impact the input voltage but my understanding is the 12 or 24 volt settings refer to the battery bank. Am I wrong about that?
You are quite correct.
The controller Alliance put in is somewhat underrated for the application it is used in. Having said that, it is rare that a solar panel ever achieves its rated power output. Usually it is more like 70%. Also, to draw the maximum current from the controller would require a nearly dead battery, which usually doesn't happen. So, in practice it will work fine.
If you wanted to buy a new controller, I would recommend a 30 amp controller to go with the 320 panel.
 
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