I see the source of your confusion now. The terminal up by the shunt is a stud on the chassis, which Forest River used for the same purpose. I just added connections to it. And the panel is also using the chassis for its negative connection. So the panel is definitely in the circuit.
I am sure I have confused some of you by the timeline of genset starts, restarts etc. I am confused myself, so sorry about that. I do know this: It was flashing the high voltage error code when it shut down, and I was able to get it restarted more than once in that condition. Which would suggest that the fuse was blown, yet it restarted!
HOWEVER, the chassis-house interconnect might have been energized by what its black box read as having charging available for the chassis battery from the house side. It saw voltage greater than X (I'm guessing X = 13.0 or so) and its logic probably says "if V>13.0, close the solenoid and divert some charging current to chassis battery". There would have been enough volts and current from the solar controller to close the solenoid. Then the chassis battery would have been tied in to the house side, allowing the genset to do restarts/attempted restarts.
That is my theory about why I could continue to run the genset starter after the fuse blew. It sort of wraps up all the loose ends except for why the fuse blew. I'd like to say it was just the draw of the cranking, but why did the genset run for a few minutes, then sense 19.6v and shut down? We may never know, as I plan to put a larger fuse on and go from there.
...i think the solar connection to the batteries belongs on the other side of that fuse,
move the solar connection or the generator connection
so that either fuse doesn't blow or solar is always connected...
Sorry to thread jack, but I hadn't considered this before but it makes sense. My solar controller is currently wired like the OP where the controller connection at the battery is on the protected side of my catastrophic failure fuse. It made sense to me at the time for EVERYTHING to be on the protected side, but I guess not?. Does a DC circuit breaker care about the direction of current to do its job?
It's my understanding that the direction does not matter to a circuit breaker.
No, the genset is definitely wired to the house battery. It did not start once the fuse blew. At the tail end of all this, the genset would not start. However its switch was still making it appear to me that it was available, this would be due to the juice coming from the solar. I did not fully describe that portion of the situation.
The terminals are all squeaky clean and tight, they all are like new.
I chose the fuse size myself. It is something I added that was not there from the factory. I do understand that it is supposed to be sized to the cables. I can't figure out what made it blow, and that bothers me.
Jrnymn: The solar is fed into the wiring prior to the fuse and battery. When the fuse blew, everything except the battery was able to get current and voltage from the solar.
I am not using the Load terminals on the controller. Just the terminals for the panels and battery. As to the negative path, everything is connected on the negative side before the batteries too.
OK, everything checks out working fine, no damage to boards or anything I can think of to try.
I tried to run the genset but it was sucking air (1/8 tank). The chattering I was hearing was the fuel pump sucking air. I can't imagine that would blow the 100A fuse though.
I drove her into town, got gas, and now the genset is running well. Like I said, everything works, I'll just have to get a new bigger fuse. And a spare.
Don, I like a fuse for that catastrophic application.
I'm back. I'll try to comment without going back and quoting all the various things I want to remember to comment on. :)
First, Mr Wizard, I agree that the solar controller to the battery needs to be after the 100A fuse. That was a big mistake, as we now see.
Question: where was the voltage reading taken? Answer: Point A. Before the battery fuse, after the controller. Tied in with everything.
Now, when the 100A fuse blew and the controller went to 19.6v, that voltage was being sent everywhere else. To the inverter (which has internal protection), to the genset controls, to the fuse panel and everywhere beyond, and possibly even to the chassis battery, depending on the logic of the little system that controls the interconnection relay. Oh, even that thing too got hit with 19.6v. If nothing blew, I'll be really lucky.
I'm having a hard time accepting that the 100A fuse blew just as the genset started. I mean, sure it could have done that. I know that the 19.6v had nothing to do with the fuse blowing. But, the genset ran for several minutes, then shut down with the error code. It seems likely that was the moment the fuse blew. But why? I wonder about what I think was a chattering relay at the genset. With all the genset noise and rattles, it was hard to say. In fact I had removed the cover on the genset was trying to pinpoint the noise when the genset shut down. Maybe it's the starter relay, and it caused the fuse to blow. I wish I knew how to troubleshoot it. It obviously works when it's time to start the genset.
BFL: As jrnymn said, I saw the 19.6v after it had been present for a few moments, THEN disconnected the panels.
ALL: Any recommendation on the size of the replacement fuse? This is all pretty new installation, and I decided on the 100A. Well, I DID use my clamp on ammeter and measured 70-some cranking amps, and that's when I decided on 100A. It's supposed to be a catastrophic fuse. Size wise, it is protecting 2 gauge cabling. It sure seems like it needs to be bigger, like 125 or 150?
My MH has been sitting in the driveway for several weeks with the solar panels keeping it charged. NO shore power. Today I went in to run the genset.
The voltage meter read 13.6v before I did anything. The battery switch was On. No appliances or systems were turned on, it was on minimal life support.
I started the genset. After a minute or so I started the AC. After another minute or two the genset shut down. It was blinking 29, which means battery voltage over 19v. Which I thought was silly. I tried to restart it a couple of times but it shut down immediately and blinked 29. I putzed around and scratched my head for a bit.
Note: While the genset was running, I thought there was a relay chattering at the genset. That has been a recurring random issue.
Then I glanced over at the voltmeter and it was reading 19.6! I immediately tripped the circuit breaker coming from the solar panels into the Morningstar SS-20 controller, and the voltmeter went blank, telling me there was no longer ANY voltage in the house.
I checked my 100A fuse at the positive post of the battery bank and sure enough, it was blown. The battery bank read 13.2v at that moment, with the house cables disconnected. That's where things stand now. Let's set aside questions of what collateral damage there might be to boards and stuff.
It sure seems to me that the controller was letting the 19.6v go right through it. Or am I jumping the gun on that? How could running the genset (and therefore the converter) have damaged the controller?
What would blow the 100A fuse? It does serve the genset starter cable as well as the house. The genset cranking amps are 70-something. The fuse is a good one, a MRBF like this:
Put it another way, is there anything other than cranking the genset which could have blown the fuse?
My plan to start troubleshooting will be to disconnect everything from the batteries except the controller, then reconnect the panels and see what kind of voltage there is. And go on from there.
Here is how I've got it wired. Obviously this is not a professional schematic. :)
The Sprinters are supposed to handle better. I drove one, but don't recall for sure. Probably true. Their cab comfort is the best of the 3. Their seats often swivel, which makes for a more versatile layout when camped.
That said, we went with the Chevy, saved a lot of money, and have the comfort of easy access to service places.
It's mostly a camping lifestyle decision. If you drive for one day to some place and camp there for a week or two, then go home, the TT is a better choice. I think a MH is more versatile though. We love ours.
Yes, I couldn't recall if it is 55 or 57. There must be a heckuva reserve in the gauge readings, because when the light comes on and it reads E, I only get 45-46 gallons into it. I know on our Chevy Duramax pickup, there is a big reserve.
I think the 200 lbs of rack and cargo on the hitch are putting a lot of weight onto the rear wheels. I would have loved to get the weights without that stuff. In any event, it handles good and like you say, there is room for another ton. Not that I want to.
This is fully loaded for camping. Food, clothes, stuff. 400 lbs of people and dog in the cab. 200 lbs of hitch rack and cargo. 40 gallons of water in various tanks.