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Electrical Question

Actually a couple of questions for the folks that can look at these electrical schematics without getting a headache. 😊
What is being shown in the highlighted area of the schematic? It looks like a distribution lug for supplying power from the house batteries.
My second question is this? Scenario "Electrical Smoke from an Unknown Source". I want to isolate all A/C and D/C power.
Obviously you turn off the Main breakers at the panel. But you still have power coming to the panel. I want to understand how to make the coach electrically "Dead".  As we say at work a "Cold dark Airplane".

1. D/C power. Does the battery switch at the front door remove "ALL" D/C power from the coach? Including the feed to the panel?  I can't tell from the schematic.
2. A/C power. Shore power- Turn off the breakers at the pedestal and unplug for redundancy.
                        Generator- Shut it down.
                        Charger/Inverter- If it has inverter mode enabled it will be supplying A/C power from the house batteries.  It looks like the Charger/Inverter is wired "Hot" to the battery.
It would also be nice to have a readily ( From Outside the Coach) available battery disconnect in the engine compartment. It's a little surprising they don't come that way from the factory. That will be on my to do list. I'll try to post pictures of the schematic.

2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Electrical Question

Reply #1 –
Quote from: Res777 –
1.  What is being shown in the highlighted area of the schematic?  I want to isolate all A/C and D/C power.
 
2.  D/C power. Does the battery switch at the front door remove "ALL" D/C power from the coach?

3.  A/C power. Shore power- Turn off the breakers at the pedestal and unplug for redundancy.

4.  Generator- Shut it down.

5.  Charger/Inverter- ?
Assuming you have no solar:

1.  Common DC power distribution point.  See the B11 000 cable that goes to positive battery post on coach batteries?

2.  NO.  To positively remove all battery power, disconnect all battery cables at the batteries.  Or, as you said, install a cutoff switch.

3.  YES

4.  YES

5.  Turn OFF the inverter/charger.  But, if you have disconnected the battery cables and cut the shore power, then the inverter is already dead.

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Electrical Question

Reply #2 –
This drawing should be easier to read and if you post the other drawing number
if I have it I will post it also.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Electrical Question

Reply #3 –
To kill ALL power, based on no solar power. 
Generator off,
Unplug from shore power.
Disconnect coach batteries
Disconnect chassis batteries.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Electrical Question

Reply #4 –
Quote from: Chuck & Jeannie –
1.  Common DC power distribution point.  See the B11 000 cable that goes to positive battery post on coach batteries?

2.  NO.  To positively remove all battery power, disconnect the battery cables at the batteries.  Or, as you said, install a cutoff switch.

3.  YES

4.  YES

5.  Turn OFF the inverter/charger.


Disconnecting would be problematic on my coach. The batteries are behind a bulkhead in the forward pass through bay behind a panel that has to be removed. So it seems to me I need two disconnects. One from the batteries to the distribution point. And one from the batteries to the Inverter. I'm starting to plan an update to the charging system from the alternator to the house batteries to include a new Charger/Inverter. I will plan on installing these two disconnects then where they are readily accessible in the bay. It seems to me the safest route if you wake up in the middle of the night choking on smoke is.
1. GET OUT of the coach!!!
2. Be able to quickly remove ALL electrical power from outside.
I'm surprised that a coach of this quality and price point didn't already have this.
There's always ONE more thing to do....... 🤷🏻‍♂️😂
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Electrical Question

Reply #5 –
Quote from: Res777 –
So it seems to me I need two disconnects. One from the batteries to the distribution point. And one from the batteries to the Inverter.
Your diagram in the first post shows two POS (+) battery cables originating on the same coach battery post.  One cable goes to common distribution point.  The other cable goes to inverter power supply 350A fuse.  To cut power to both circuits would only require one switch located near the coach battery.

Photo below shows the setup on our old coach.  The red main battery disconnect switch is located in battery compartment behind driver side rear wheels.  I can turn off battery power to all house battery circuits and the inverter from outside the coach.  Good when time is a factor.  We also have solar so the two smaller switches cut off the feed from the panels to the controllers.

Blue Sea Systems makes excellent battery switches in several configurations (manual and remote control).  Check out what they offer:

Battery Switches - Blue Sea Systems

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Electrical Question

Reply #6 –
Quote from: Chuck & Jeannie –
Your diagram in the first post shows two POS (+) battery cables originating on the same coach battery post.  One cable goes to common distribution point.  The other cable goes to inverter power supply 350A fuse.  To cut power to both circuits would only require one switch located near the coach battery.

Photo below shows the setup on our old coach.  The red main battery disconnect switch is located in a rear wheel well.  I can turn off battery power to all house battery circuits and the inverter from outside the coach.  Don't even need to open a storage bay door.  Good when time is a factor.  We also have solar so the two smaller switches cut off the feed from the panels.

Blue Sea Systems makes excellent battery switches in several configurations (manual and remote control).  Check out what they offer:

Battery Switches - Blue Sea Systems

Wouldn't he need a cable going to the switch from the battery with equal capacity of the 2 cables going there now?
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: Electrical Question

Reply #7 –
Quote from: Chuck & Jeannie –
Your diagram in the first post shows two POS (+) battery cables originating on the same coach battery post.  One cable goes to common distribution point.  The other cable goes to inverter power supply 350A fuse.  To cut power to both circuits would only require one switch located near the coach battery.

Photo below shows the setup on our old coach.  The red main battery disconnect switch is located in battery compartment behind driver side rear wheels.  I can turn off battery power to all house battery circuits and the inverter from outside the coach.  Good when time is a factor.  We also have solar so the two smaller switches cut off the feed from the panels.

Blue Sea Systems makes excellent battery switches in several configurations (manual and remote control).  Check out what they offer:

Battery Switches - Blue Sea Systems


Good point. I didn't think about that. Thanks!
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Electrical Question

Reply #8 –
Quote from: craneman –
Wouldn't he need a cable going to the switch from the battery with equal capacity of the 2 cables going there now?
Yes - I guess so - or perhaps 2 short cables from battery to switch.  But I think they make switches with 2-in and 1 or 2-out.  500 amp (continuous) rating should be sufficient.

HD-Series Heavy Duty Selector Battery Switch - Blue Sea Systems


1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Electrical Question

Reply #9 –
Yes. Like this one.
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Electrical Question

Reply #10 –
Deferent people have different preferences but I prefer to have the shortest-possible cables (positive and negative) and no switches between the starting-battery bank and the starter. I want the lowest-possible resistance to current flow when starting the engine.
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186
 

Re: Electrical Question

Reply #11 –
It would be interesting to know what the resistance of a disconnect is. I will measure it when I receive one. My thought after reading about a member that had a high heat event from a shorted isolator that it would be nice to be able to remove all power to the isolator if needed. Quickly and safely. Just a thought.
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee