600+ watt draw from phantom source!

[shrubshaker]

Hello again!

Being a new RV owner and novice in the solar industry I have a dilemma and question.



As I mentioned in my previous post, we just bought and RV (used). Here’s how the solar system is set up in the converter box and directions according to the lady we bought it from.



In converter box there is a 15 amp breaker (3rd from left in picture) and we were told when it’s on it’s charging the batteries and when it’s off we’re using solar power directly, no juice from the batteries is being used.



I’ve been having problems with our battery system only lasting 3 to 4 hours a night. So this morning I started hunting around for the problem.



I unplugged everything in the RV but the inverter still showing 620w draw when the breaker in the converter box is on.

I turned off all the breakers and confirmed there was zero draw on the inverter. Turned the breakers back on except for the solar breaker in the converter box and no draw.

Then I started plugging a fan and a couple of other things in with the 15amp breaker off and the expected draw of 150w showed on the inverter.

I turned the converter box breaker back on with the fan and other things still plugged in and the inverter showed 770w draw… Oh I forgot to mention that the fridge and water heater are running on gas, no electric draw.

What is eating up all that power, 620 watts worth, when the solar breaker in the converter box is on and nothing in the RV is plugged in? I don’t get it…

 

[Mattb4]

Sorry but it is hard to figure out your setup based on information provided. For one it does not make sense that solar has anything to do with your breaker in the converter panel.

Typical setup for RV without solar, but having a converter/charger to supply 12v loads and charge the battery, would be Shore power in (off one breaker to panel, or just the panels bus bar, and from that a breaker supplies the AC to DC converter) and other panel breakers serve any AC voltage loads. From the converter will be leads going to the DC fuses and battery. if you have an inverter it will be separate from this with input from the panels to SCC (may be an AIO) and than to the battery to charge. From the inverter to supply AC loads would require a means of switching between shore power and inverter power.

BTW, 600w/12vDC would give a 50a charge rate to battery. Which is what I suspect is going on.

 

[shrubshaker]

BTW, 600w/12vDC would give a 50a charge rate to battery. Which is what I suspect is going on.

Ok that makes sense where the 600w is going. I just don't understand why the RV would be wired to draw power from the batteries to charge themselves. Killing the batteries in the process. Ok I think I'll have to call an RV tech out to check out the system wiring setup. Thank you for your reply!

 

[TacomaJoe]

My guess is that the 15A breaker is to the converter. I have a manual transfer switch between shore and my inverter. When I'm on the inverter, I turn off the converter to break the loop.

 

[Mattb4]

My guess is that the 15A breaker is to the converter. I have a manual transfer switch between shore and my inverter. When I'm on the inverter, I turn off the converter to break the loop.

OK I get it now. The advice from previous RV owner to turn off power to the converter (15a breaker) when running from PV/inverter input. That makes sense. No need for power from the converter when operating that way. Plus which you get the rather strange situation of using solar DC to battery/inverter than AC, to converter for AC to DC to battery output.

 

[shrubshaker]

Excellent! Thank you both gents for your help