Skip to main content ↑ ↓
Topic: No [not chassis, HOUSE] battery power at inverter (Read 636 times) previous topic - next topic

No [not chassis, HOUSE] battery power at inverter

It's been hot in Vegas for the last week or so.  109 is the high today.  I run two 10k BTU portable A/C's plus two circulating fans in my coach to try to keep the load off the roof A/C's, which are set to come on at 90*F.  The portables are set to 75*F, to get ahead of the heat.  The coach is plugged in to my shop, which also has A/C's and the pool pump runs from it.  Monday, all the load popped the breaker and the coach started running on the inverter.  The roof A/C's don't run, but the fans and portables kept going.  Got home and it was about 100*F inside.

Reset the breaker and shore power is restored.  I noticed that the Xantrex is reporting that it's only charging 1amp and the dash cig lighter is showing 12.8V.  I checked the Victron BMV-712 and it's showing -1amp draw, not charging.  I discovered that there is not 12V at the end of the cables from the house batteries to the inverter.

I checked continuity across the 350A fuse in the front bay, curb side, and it's good.  Have not yet got to the batteries, and did not have a ground to check for voltage at the fuse, I'll get to that tonight (in the 105*F it will be at 8pm).  The BMV-712 shunt is showing proper voltage, so I don't think it's a battery or connection issue.

My question is, what else is in-line between the batteries and inverter besides the fuse?  The schematic in the owners manual doesn't show anything else.

[Edited topic title - Michelle]
Keith
2003 U320 38' #6197

Re: No chassis battery power at inverter

Reply #1 –
Continuity might not show that the fuse isn't passing load. I spent 2 days last year trying to find the same issue and it turned out to be the fuse.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: No chassis battery power at inverter

Reply #2 –
Back to the basics. This is in the no start category for me. I still like using a test light bulb with two leads and clips at the end. If you put across a cable that is good, light bulb out. Go across a resistance or open and it lights up. Dont forget this could also be a ground issue too. Keith dont forget I have that DC clamp on amp meter if you need it. We are leaving Saturday to North Carolina though and its part of the coach tool kit

Re: No chassis battery power at inverter

Reply #3 –
Thanks guys, I'm suspecting the fuse as well.  It was the only thing I saw that it could be.  I'll pull it out tonight and look it over closer.  I should have a spare and don't.  Anyone know where to get this 350A thing?
Keith
2003 U320 38' #6197

Re: No chassis battery power at inverter

Reply #4 –
Quote from: WS6_Keith –
  Anyone know where to get this 350A thing?

I would check Digi Key, Allied, or Dell City. There are several styles so the one you have could be different than ours. So in other words it is a Easter egg hunt but those electric supply companies will have them.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: No chassis battery power at inverter

Reply #5 –
Quote from: WS6_Keith –
My question is, what else is in-line between the batteries and inverter besides the fuse?  The schematic in the owners manual doesn't show anything else.

Noting that you're asking about chassis batteries, unless you have something like a Trik-l-start or other added charging relay, or are using the boost switch, the OEM Xantrex inverter/charger and wiring in a 2003 does not charge the chassis batteries, only the house ones.

If you don't have the OEM setup, the above may not apply.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: No chassis battery power at inverter

Reply #6 –
From a bit of searching, it looks like the fuse is a Class T format, 350A.  My Xantrex inverter is supposed to provide 3000w continuous and 6000w peak.  At 12V, that's 250A/500A.  It could never produce the peak with this fuse in place.  Should I be considering getting a higher amperage fuse?  I assume the fuse is really there to safeguard a dead short during an accident or something similar, so it would pop a 500A as easy as a 350A, but under load, you wouldn't pop a 500A as easy as that 350A.  I've had this thing 3 years and this is the first issue, but I don't want to repeat it either.  The fuses look to be around $75ish.
Keith
2003 U320 38' #6197

Re: No chassis battery power at inverter

Reply #7 –
Quote from: Michelle –
Noting that you're asking about chassis batteries, unless you have something like a Trik-l-start or other added charging relay, or are using the boost switch, the OEM Xantrex inverter/charger and wiring in a 2003 does not charge the chassis batteries, only the house ones.
You're right.  Edited.  HOUSE batteries.
Keith
2003 U320 38' #6197

Re: No chassis battery power at inverter

Reply #8 –
Quote from: WS6_Keith –
You're right.  Edited.  HOUSE batteries.

I've edited the topic title  :D
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: No [not chassis, HOUSE] battery power at inverter

Reply #9 –
Quote from: WS6_Keith –
Should I be considering getting a higher amperage fuse? 

Keith,

Look at the size of your cables, Will they handle that many amps?  If not then the cable will become the fuse if you put in a larger size fuse.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: No [not chassis, HOUSE] battery power at inverter

Reply #10 –
The fuse is definitely the issue.  I ran a wire from the ground to my meter and then probed both sides of the fuse.  Input has 13.04V, output had 12.6, then started dropping.  Still being connected to the inverter at the other end, I'm guessing there was a charged capacitor back feeding some voltage.  It's 0V now and shows no continuity.

Those cables are 3/0.  I'll just stick with the 350A fuse and get a spare. 
Keith
2003 U320 38' #6197

Re: No [not chassis, HOUSE] battery power at inverter

Reply #11 –
Replacing the fuse seems to have put everything back in working order.  The old one does show discoloration indicating it's been hot, maybe that was part of the issue.  No idea how old it is, it could be original for all I know.

Keith
2003 U320 38' #6197

Re: No [not chassis, HOUSE] battery power at inverter

Reply #12 –
I spent 2 days trouble shooting the blown fuse issue and should know do the simplest things first. I even ordered 2 spares after that.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: No [not chassis, HOUSE] battery power at inverter

Reply #13 –
I have added a spare to my stash as well.  I'm slowly catching up to DSD with the "spare coach in the coach" plan.
Keith
2003 U320 38' #6197

Re: No [not chassis, HOUSE] battery power at inverter

Reply #14 –
Quote from: WS6_Keith –
I have added a spare to my stash as well.  I'm slowly catching up to DSD with the "spare coach in the coach" plan.
please send me a link to the fuse. I don't want to be left out without one.

Re: No [not chassis, HOUSE] battery power at inverter

Reply #15 –
Quote from: dsd –
please send me a link to the fuse. I don't want to be left out without one.
Haha!  Here you go Scott:

Amazon.com: Blue Sea Systems 5120 FUSE A3T (CLASS T) 350-AMP : Tools & Home...
As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
Keith
2003 U320 38' #6197

Re: No [not chassis, HOUSE] battery power at inverter

Reply #16 –
Quote from: WS6_Keith –
I have added a spare to my stash as well.  I'm slowly catching up to DSD with the "spare coach in the coach" plan.

 :coffee:  *wondering how to create a usable "spare parts by generation" info repository...  need more  :coffee:  *
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: No [not chassis, HOUSE] battery power at inverter

Reply #17 –
Quote from: Michelle –
:coffee:  *wondering how to create a usable "spare parts by generation" info repository...  need more  :coffee:  *
Some of the basics would be:

    • spare of every belt (eng and gen)
    • at least a gallon of coolant, trans fluid and engine oi
    • air compressor parts (I carry reeds for my Air-Zenith pump)
    • assortment of Robertson and Philips screws
    • house water pump
    • assortment of blade and glass fuses
    • A/C capacitor
    • house battery fuse
Keith
2003 U320 38' #6197