Strange electrical/Breaker issue (solar related??)
This is on my 2015 Thor Majestic 28a. I've owned for over a year and haven't had any fuse/breaker/electrical issues. Everything works exactly as it is supposed to.
My battery bank consists of two Group 29D 100AH lead acid batteries. I will be adding one more to help with heavier loads on the inverter.
Recently, I added 500w of solar and a 2000w pure sine wave inverter. Here is what the setup looks like...
Two 250w residential solar panels wired in parallel on the roof (~36v @ 8.2a each under ideal conditions).
Connected through a 40 amp resettable fuse to an EPEVER 30 amp MPPT solar charge controller.
The output of the solar charge controller goes through a 40 amp resettable fuse. After about 2 feet, it connects to the +/- terminals on the 2000w inverter. From there there are a double pair of 2/0 cables going ~8 feet to my battery bank (to be able to carry the potentially heavy load of the 2000w inverter).
I have an Aili battery monitor hooked up so I can monitor the battery bank voltage and current flowing in/out of the batteries. Works great and as expected.
Everything seemed to be functioning fine and as expected. I could see that the solar is charging the batteries (highest amps I have seen so far going into the batteries is about 23 amps, but I never looked yet at high noon). The 2000w inverter works when I plug various things in up to about 600-700w (I've only got two deep cycle Group 29D lead acid batteries and will be adding another soon to help with heavier loads).
I wanted to do a solar charging test recently, so overnight I drained my 200AH battery bank to about 50%. I wanted to see if the next day (which was sunny) the solar would charge the batteries all the way up to full. Nothing was on inside the RV and nothing was plugged into the 2000w inverter. Well, I went to check on the batteries in the afternoon. The battery monitor was at ~80-85% (can't remember exactly). But the interesting thing was that the 40 amp resettable fuse between the solar charge controller output and the inverter +/- terminals (which are hooked up to the battery bank) had popped. I thought this was strange as the MPPT controller is 30amp and I assumed had a maximum output of 30 amps.
I wondered...could there have been anything driving the current back towards the solar charge controller and popping the 40amp breaker? I didn't think so. Could the 30amp charge controller have delivered more than 40 amps??
Let's do some math... The panels (in parallel) each have a max voltage of 36v and max output of 8.2amps. If the solar charge controller during a particular stage is trying to charge the batteries at 13.6v, then (if I'm not mistaken) the 36v at 16.4amps could get converted into 36v/13.6v = 2.65 multiply the 16.4 amps could generate 43.46 amps. (Yes, I know my charge controller could be limiting my solar output, but I don't really care about efficiency as I was only planning on putting on 250w in the first place and I've only got 200AH of battery bank for now). I suppose if the 30a MPPT controller actually delivers this ~43 amps, it would in fact pop the 40a resettable breaker. Do you think this is what happened?? Do any of you have a MPPT solar charge controller that actually delivers ABOVE the advertised max output?
Then I thought, well...since the solar charge controller output is connected to the battery bank (via the terminals of the 2000w inverter), I really don't care if it is delivering MORE than 40 amps to the batteries, so I changed the 40 amp breaker (between the solar charge controller and the terminals on the inverter) to 50 amps. I was hoping this would fix the issue. Maybe there was a spike of some sort(?) on the charge controller output that was more than 40amp that popped the breaker and maybe going to a 50amp breaker would resolve the issue.
But then, just today there was a new issue I had never seen before. And this one has me scratching my head...and I wonder if it has anything to do with the solar/inverter install I recently did. I have a friend using my RV and he was at a full hookup campsite last night. Note: He is very unexperienced at RVing so who knows if he plugged in/out correctly, etc. This morning when he unhooked everything he told me that all of the 12v items were no longer working (interior lights, water pump, refrigerator on propane). As a test, I had him turn on the generator...everything worked (120v and 12v lights, water pump, etc). But as soon as he turned off the generator the 12v items stopped working. I ran him through all the usual things to check. I was able to find the fix. The main CONVERTER BREAKER (I believe it is also 40 amps) had popped. I believe this breaker is the master control for the 12v wire going into the converter that goes to all 12v systems. Here is a picture:
*** What are the most typical situations that pop this CONVERTER BREAKER? ***
Note: Because of their lack of experience, I suppose it is possible that this actually popped anytime in the last 24hrs (and maybe they only noticed it after they unplugged in the morning). If they got to the campsite yesterday in the daylight, they might not have even noticed (before plugging in to shore power) that the 12v wasn't working. To me, it doesn't seem like anything from the solar/inverter install should cause this. Afterall, the solar/inverter simply tie into the battery bank much the same as, for example, the chassis alternator (which can deliver 50-100 amps). What do you think?
I welcome your thoughts on the matter.
Thanks!
Chris
My battery bank consists of two Group 29D 100AH lead acid batteries. I will be adding one more to help with heavier loads on the inverter.
Recently, I added 500w of solar and a 2000w pure sine wave inverter. Here is what the setup looks like...
Two 250w residential solar panels wired in parallel on the roof (~36v @ 8.2a each under ideal conditions).
Connected through a 40 amp resettable fuse to an EPEVER 30 amp MPPT solar charge controller.
The output of the solar charge controller goes through a 40 amp resettable fuse. After about 2 feet, it connects to the +/- terminals on the 2000w inverter. From there there are a double pair of 2/0 cables going ~8 feet to my battery bank (to be able to carry the potentially heavy load of the 2000w inverter).
I have an Aili battery monitor hooked up so I can monitor the battery bank voltage and current flowing in/out of the batteries. Works great and as expected.
Everything seemed to be functioning fine and as expected. I could see that the solar is charging the batteries (highest amps I have seen so far going into the batteries is about 23 amps, but I never looked yet at high noon). The 2000w inverter works when I plug various things in up to about 600-700w (I've only got two deep cycle Group 29D lead acid batteries and will be adding another soon to help with heavier loads).
I wanted to do a solar charging test recently, so overnight I drained my 200AH battery bank to about 50%. I wanted to see if the next day (which was sunny) the solar would charge the batteries all the way up to full. Nothing was on inside the RV and nothing was plugged into the 2000w inverter. Well, I went to check on the batteries in the afternoon. The battery monitor was at ~80-85% (can't remember exactly). But the interesting thing was that the 40 amp resettable fuse between the solar charge controller output and the inverter +/- terminals (which are hooked up to the battery bank) had popped. I thought this was strange as the MPPT controller is 30amp and I assumed had a maximum output of 30 amps.
I wondered...could there have been anything driving the current back towards the solar charge controller and popping the 40amp breaker? I didn't think so. Could the 30amp charge controller have delivered more than 40 amps??
Let's do some math... The panels (in parallel) each have a max voltage of 36v and max output of 8.2amps. If the solar charge controller during a particular stage is trying to charge the batteries at 13.6v, then (if I'm not mistaken) the 36v at 16.4amps could get converted into 36v/13.6v = 2.65 multiply the 16.4 amps could generate 43.46 amps. (Yes, I know my charge controller could be limiting my solar output, but I don't really care about efficiency as I was only planning on putting on 250w in the first place and I've only got 200AH of battery bank for now). I suppose if the 30a MPPT controller actually delivers this ~43 amps, it would in fact pop the 40a resettable breaker. Do you think this is what happened?? Do any of you have a MPPT solar charge controller that actually delivers ABOVE the advertised max output?
Then I thought, well...since the solar charge controller output is connected to the battery bank (via the terminals of the 2000w inverter), I really don't care if it is delivering MORE than 40 amps to the batteries, so I changed the 40 amp breaker (between the solar charge controller and the terminals on the inverter) to 50 amps. I was hoping this would fix the issue. Maybe there was a spike of some sort(?) on the charge controller output that was more than 40amp that popped the breaker and maybe going to a 50amp breaker would resolve the issue.
But then, just today there was a new issue I had never seen before. And this one has me scratching my head...and I wonder if it has anything to do with the solar/inverter install I recently did. I have a friend using my RV and he was at a full hookup campsite last night. Note: He is very unexperienced at RVing so who knows if he plugged in/out correctly, etc. This morning when he unhooked everything he told me that all of the 12v items were no longer working (interior lights, water pump, refrigerator on propane). As a test, I had him turn on the generator...everything worked (120v and 12v lights, water pump, etc). But as soon as he turned off the generator the 12v items stopped working. I ran him through all the usual things to check. I was able to find the fix. The main CONVERTER BREAKER (I believe it is also 40 amps) had popped. I believe this breaker is the master control for the 12v wire going into the converter that goes to all 12v systems. Here is a picture:
*** What are the most typical situations that pop this CONVERTER BREAKER? ***
Note: Because of their lack of experience, I suppose it is possible that this actually popped anytime in the last 24hrs (and maybe they only noticed it after they unplugged in the morning). If they got to the campsite yesterday in the daylight, they might not have even noticed (before plugging in to shore power) that the 12v wasn't working. To me, it doesn't seem like anything from the solar/inverter install should cause this. Afterall, the solar/inverter simply tie into the battery bank much the same as, for example, the chassis alternator (which can deliver 50-100 amps). What do you think?
I welcome your thoughts on the matter.
Thanks!
Chris
