Please help explain how the solar works

[chezwick]

So, I have a 2023 Northpoint 377 RLBH. I have two factory 200 watt solar panels on the roof the factory charge controller and inverter. Not only will this solar setup not run my residential fridge for more than a few hours ( which is understandable ( I guess ) but it won’t even keep the batteries charged.

So, when I park the camper for a normal break of 2-3 weeks until the next use, I make sure the inverter is on with the BM Pro and it will say “inverting “ I will come check it a few days down the road and it’s in fault mode or the batteries are just totally dead !
Now I hV3 a complexed solar and micro hydro system with multiple inverters and batter6 system that runs my whole home and that system doesn’t give me near the grief this imple little RV system does. I had the entire BM Pro mother board replaced ( from a totally unrelated issue ) and the charge controller replaced by the dealership. I still have the same issue
So what’s the secret to getting this system to work properly?

[Jayhawk 29]

Tell us the particulars on your batteries. This may be the weak link. 2 to 3 hrs for starters screams minimal battery capacity. Of course when my camper is not in use, the residential fridge is not left on. And I make sure i turn the dedicated breaker off so that there is no light consuming power with the doors open.

[chezwick]

Yeah, I’m sure my batteries are the weak point in allowing the fridge to run for more than 2-3 hours. They are 2 lead acid. However, they were just replaced when the charge controller was replaced. I would think, no I actually expect this solar system to at a minimum keep the batteries charged when not in use. We do turn off the fridge but do not flip the breaker. If this solar system can not handle a super small red led light on the fridge then what’s the point ?

[Tadsher]

If the lead acid batteries were allowed to go completely dead then the lead acid batteries are junk, new or not new, I would recommend that you upgrade to LIFEPO4 batteries. The solar controller and the converter would need to be appropriately set for the new batteries.

[Jayhawk 29]

Originally Posted by chezwick

Yeah, I’m sure my batteries are the weak point in allowing the fridge to run for more than 2-3 hours. They are 2 lead acid. However, they were just replaced when the charge controller was replaced. I would think, no I actually expect this solar system to at a minimum keep the batteries charged when not in use. We do turn off the fridge but do not flip the breaker. If this solar system can not handle a super small red led light on the fridge then what’s the point ?

I don't know the brand of your controller and your solar panels, but a lot of controllers have a float and flood setting that might contribute to your batteries not being fully charged. The angle of the sun in your local area can play a role in not allowing the panels to put out its full potential ratings either. What size are your batteries? This also deals with AH ratings.

And yes if they are drained down to far for repeated cycles at some point, then you may still have a weak link. When you say red light, I don't recall my 110 fridges just having a small red light on when being turned off by just turning the fridge off internally.

You also have other digital standby power usage such as your radio, and your monoxide detector. An inverter can be on standby, which some causes a drain too.

[Stan&Sharon]

If you want to know, at your current rate of discharge, how many hours your battery will last before you reach 50%, you might consider adding this Victron Smart Shunt.

This connects inline to the negative battery cable. Here is what I see on a phone:

Notice it shows I have 8hours and 19minutes remaining as well as current usage. This shows in real-time so you can decide which appliances to use and their impact.
If you don't have lithium batteries, you'll want to avoid exceeding 50% on your battery. I went from one to three lead acid batteries before I switched to this single lithium in October 2022. Now I have this one and it's just what I need. If you plan to boondock or want to stay off shore power for more than a night, you'll want to get more amp hours. The shunt mentioned above can help you calculate how much.

[AZDIESELPIG]

Originally Posted by chezwick

So, I have a 2023 Northpoint 377 RLBH. I have two factory 200 watt solar panels on the roof the factory charge controller and inverter. Not only will this solar setup not run my residential fridge for more than a few hours ( which is understandable ( I guess ) but it won’t even keep the batteries charged.

So, when I park the camper for a normal break of 2-3 weeks until the next use, I make sure the inverter is on with the BM Pro and it will say “inverting “ I will come check it a few days down the road and it’s in fault mode or the batteries are just totally dead !
Now I hV3 a complexed solar and micro hydro system with multiple inverters and batter6 system that runs my whole home and that system doesn’t give me near the grief this imple little RV system does. I had the entire BM Pro mother board replaced ( from a totally unrelated issue ) and the charge controller replaced by the dealership. I still have the same issue
So what’s the secret to getting this system to work properly?

What kind of Fridge do you have? We have a residential 12v fridge and the 2 batteries on solar can not keep up with it past a week or so. i usually keep it plugged in to the 50amp at the house but if i don't I turn the inverter OFF so the fridge is not powered on.

[Learjet]

what is the solar output on the energy screen when you are generating solar electricity. Why would you leave the inverter on if you are not using the RV?

[wjadma]

I don't believe that just 200 watts will power the trailer

[Go-red-car]

I have 400w of Solar with 2x100 AH lithium batteries. I do not have an AC only fridge so this setup works pretty well.

I always shut off my inverter when I’m not using AC as there is a constant loss when it is on. Additionally you need to make sure that your converter is off or you create a parasitic loop with battery source powering inverter which powers the converter which attempts to charge batteries ��.

If you don’t need your fridge on when in storage mode I would turn off the inverter.

[Jayhawk 29]

Originally Posted by Go-red-car

I have 400w of Solar with 2x100 AH lithium batteries. I do have an AC only fridge so this setup works pretty well.

I always shut off my inverter when I’m not using AC as there is a constant loss when it is on. Additionally you need to make sure that your converter is off or you create a parasitic loop with battery source powering inverter which powers the converter which attempts to charge batteries 🤪.

If you don’t need your fridge on when in storage mode I would turn off the inverter.

A slightly different direction when using a 110 fridge on the inverter, in conjunction to my 600 watts of solar and two GC 2 6 volt flooded batteries, 232ah ,I turn the fridge up above normal run setting during the day, when the batteries are being charged to the potential outside element max and let it really cool down inside. Then at night I turn the fridge back down in the night time.

This means the fridge maintains the temps when not being open during the waking hours and consumes less power, with or without the inverter on.

[garywilson]

Originally Posted by chezwick

So, I have a 2023 Northpoint 377 RLBH. I have two factory 200 watt solar panels on the roof the factory charge controller and inverter. Not only will this solar setup not run my residential fridge for more than a few hours ( which is understandable ( I guess ) but it won’t even keep the batteries charged.

So, when I park the camper for a normal break of 2-3 weeks until the next use, I make sure the inverter is on with the BM Pro and it will say “inverting “ I will come check it a few days down the road and it’s in fault mode or the batteries are just totally dead !
Now I hV3 a complexed solar and micro hydro system with multiple inverters and batter6 system that runs my whole home and that system doesn’t give me near the grief this imple little RV system does. I had the entire BM Pro mother board replaced ( from a totally unrelated issue ) and the charge controller replaced by the dealership. I still have the same issue
So what’s the secret to getting this system to work properly?

I don't know about yours, but my inverter draws lots of power even if nothing is using it. It will draw a new flooded 12V battery to nothing in less than 10 hours.

[Wonderment]

If you're just trying to maintain the battery charge in between uses, you need to make sure the solar charge controller is on and the inverter is off.

[rkonvicka]

I have the same setup and our trip to the mountains, no hookups was interesting. *I did add a third battery and added two extra panels I could move around on the ground, 200 Watts. *First spot we got was perfect settled in and low and behold trees above us totally blocked over half the days sun. *Luckily I could move the 2 on the ground around and keep us going all day. *But batteries wouldn't last much into the night. *All in all i was making 130 amp hours a day which kept everything going but left nothing to go back into the banks. *10 amps of charging current needed to be 30 amps. *large fridge only drew about 10 amps from batteries when running, small fridge maybe 5 amps. *The BMPro system monitors that pretty well.* *But monitors nothing from the 12 volt devices drawing power.

I have 300 amp hour capacity on batteries and 30 amps charging capacity from solar, but thats under perfect conditions. *Trees clouds rain angle of the sun all contribute to far less than ideal charging conditions, count on half.

With inverter off you should be able to keep those batteries topped off, 20 amps of charging current is what you should be getting during the day.
Getting enough sun? Panels dirty? Whats your average amp hour charge going back to the batteries? Maybe a draw somewhere your not aware of? Do you have the camera system, is that off? Winguard off?
You could plug it in charge up fully and load test batteries, another weak spot your 100 amp hour batteries might be 50 amp hour capacity due to age or condition of battery. All in all if you can measure whats going in and whats coming out, should give you an idea of whats going on.

I plan on installing a smart shunt as stan mentioned to see draw from 12 volt devices and upgrading my 110vac converter to charge at 100 amps from generator power and maybe upgrade batteries to 400 amp hours of lithium.
Ricky Konvicka

[Solly]

I had this exact problem. Dealer replaced controller twice to no avail. I took it apart and read the manual. The red and black wires were "correct" but when I reversed them all was well. Apparently it is wired wrong at the panel. As I recall I did some tester work before I just started switching wires.