2 apr snafu inverter wiring fix Sunday evening 9pm
i hate to admit this, but i also believe in owning up to your mistakes, and others can learn from that.
I’ve been frustrated at how much my inverter draws when I turn it on. so i was grousing about it to Jeff. and when I told him it was consuming like 500 watts he was like WHAT!?!?!? for comparison, his draws 30watts at no load. No load, means it's inverting, but you aren't running anything off the ac power you're making,
after some discussion, it seemed to me like what was happening is that when I turn the inverter on, my rv distribution panel (breaker box) was charging the batteries. think of it like eating your own arm because you’re hungry. not an efficient way to do things.
so I was losing battery power to the inverter converting 12 volt battery power to household 120volt current. then I was losing power to the rv panel converting the 120v power from the inverter back to 12v to charge batteries.
my first idea was to cut the dc power lines on the back of the rv dist. panel to the bus bar. The bus bar is where all my Victron stuff connects. The inverter, solar panel charge controller, the alternator dc charge controller, and the batteries.
the bus bar has a thick metal bar for all the positive connections and another thick bar for the negative. When I cut the rv dist panel’s dc wires to the bus bar I lost all dc power. Duh…(not sure what I thought that would fix in retrospect) i’ll blame it on doing this at the end of a long day, but trial and error I suppose.
then it dawned on me that i should just turn off the 15amp 120v breaker that feeds the rv panel’s circuit board that charges the battery. I then reconnected the wires i previously cut and voila!
the inverter now only uses 9watts with no load. when I use the 800 watt hot water kettle it pulls about 850 watts. (the more you pull the more power wasted in the AC/DC conversion). Before the fix, it was pulling 1400 watts when I used the 800 watt kettle. not good.
like i said i wasn’t actually losing the 500 watts before because about 450 watts was going back into the batteries. however, i was losing 500 watts of the 2000watt inverters capacity to make AC power because 500 watts were going right back into the batteries (dumb).
luckily my hot water kettle is only 800 watts, and my instant pot is 1000watts. which is probably why I hadn’t figured this out yet. I’ve never tried to use the full capacity of the inverter.
part of the reason i made the mistake is because I’d copied my micro campers wiring, but it doesn’t have an inverter. so when you have an inverter, don’t add the ac breaker to power the circuit board in your rv breaker box. BUT you still have to connect the dc power lines off the back of the rv panel to the bus bars.
apologies if that was all blah blah blah, but i wanted to get it off my chest.
none of the above was dangerous. i hadn’t done anything that would’ve burned the truck down. just explaining my mistake, but that’s how you learn.
the only part I’ll pat myself on the back about is having all the tools, including some spare WAGO electric connectors to troubleshoot this in the field. not as good as jeff’s sewer pipe fix, but i’ll take it.
From the future: adding these photos to show the inverter that's in my rv distribution panel in the truck. It's now completely removed. I swapped it out with the mini camper's rv distribution panel because it's newer and has a dip switch to charge batteries at the higher voltage lithium iron phosphate batteries need.
