Battery Cutoff switch

> Since I’m getting back into all the battery and grounding issues on my coach was also wanting to install a battery cut off switch for my storage
> of it. Any suggestions on how and where. Seemed like I remember up by the isolator, just don’t recall which cable I interrupt there?
>
> Thanks,
> Tom
> 76 Eleganza 2
> Kansas City, Mo

http://www.gmccoop.com/the-🏁-co-op-and-the-beat-goes-on/

Check this post, it has a good picture of cutoff switch mounting.

--
JD Lisenby- USAF Ret
1978 Royale-455
MacDash, Manny Tranny, FI-tech, 3.70 etc etc

Navarre, FL
 
Looks good. My arrangement of relay’s and solenoids looks a bit different but I can see how its put together. Like I’ve said before, not super
whippy with electrical stuff. I do have a question on the placement of the cutoff switches. I like this arrangement from the aspect of shutting
everything down from one spot, especially if there was a emergency. I’ve read some guys want to have these nearest to the battery, why would that
be?

Thanks,
TG
 
Given the number of Chinese parts showing up these days, I'd suggest having a look at your disconnect switch with a temp gun during or
immediately after cranking. Any increased temp would be reason to suspect the integrity of the switch.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
Last edited by a moderator:
I don't believe you should EVER run the STARTER current through a cutoff
switch. I have never seen a switch capable of the currents (300+ Amps)
that is required by a starter.

Primary path to starter should be through a starter solenoid relay connected
directly to the positive terminal of the battery. The solenoid IS capable of
passing the hundreds of Amps that will be required for starting.

The current to the relay that actuates the starter solenoid SHOULD be supplied
via the cutoff switch.

I believe Jim Bounds has schematics of the best way to wire your starter system.

D C "Mac" Macdonald
Amateur Radio K2GKK
Since 30 November '53
USAF and FAA, Retired
Member GMCMI & Classics
Oklahoma City, OK
"The Money Pit"
TZE166V101966
'76 ex-Palm Beach
k2gkk + hotmail dot com
________________________________
From: Gmclist on behalf of Johnny Bridges via Gmclist
Sent: Friday, July 10, 2020 07:51
To: gmclist
Cc: Johnny Bridges
Subject: Re: [GMCnet] Battery Cutoff switch

Given the number of Chinese parts showing up these days, I'd suggest having a look at your disconnect switch with a temp gun during or
immediately after cranking. Any increased temp would be reason to suspect the integrity of the switch.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
Last edited by a moderator:
As I said earlier, different desires get different solutions. The daughter's car drops on the order of three millivolts across the knife switch.
Likely a minor bit more for the 455 starter, In that it's not engaged for any great length of time, and in that it's inspected on the contacts
regularly, I'll keep it on the negative battery terminal. Otherwise, the system isn't cold when the switch is open, there are/is energized wire.
Worse'n that, the energized wire is heavy enough that the inadvertent screwdriver is likely to blow the battery up. None fer me, thanks when I propped
the spray plane, "Make it COLD" got "Switch Off" and still pulled it through one handed so I could let go if there as something for the impulser to
light. "Make it HOT" got "Contact" and I knew it was gonna run.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
My starter has run through a cutoff switch for 15 years. It is kind of hard to isolate the battery if you do not run everything through the switch.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
My starter has run through a knife switch for over 20 years with no problem.

Emery Stora
77 Kingsley
Frederick, CO

>
> My starter has run through a cutoff switch for 15 years. It is kind of hard to isolate the battery if you do not run everything through the switch.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
That is the point of a disconnect. To remove all chance of accidental
connection with the + post of the battery (s). The positive side is the
correct side to interrupt. If it is open, there is no chance of accidental
shorting to ground (-).
Jim Hupy
Salem, Oregon

On Fri, Jul 10, 2020, 8:07 PM Emery Stora via Gmclist <

> My starter has run through a knife switch for over 20 years with no
> problem.
>
> Emery Stora
> 77 Kingsley
> Frederick, CO
>
> > On Jul 10, 2020, at 2:31 PM, Ken Burton via Gmclist <

> >
> > My starter has run through a cutoff switch for 15 years. It is kind of
> hard to isolate the battery if you do not run everything through the
> switch.
> > --
> > Ken Burton - N9KB
> > 76 Palm Beach
> > Hebron, Indiana
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
> Looks good. My arrangement of relay’s and solenoids looks a bit different but I can see how its put together. Like I’ve said before, not
> super whippy with electrical stuff. I do have a question on the placement of the cutoff switches. I like this arrangement from the aspect of
> shutting everything down from one spot, especially if there was a emergency. I’ve read some guys want to have these nearest to the battery, why
> would that be? My house battery is back by the generator.
>
> Thanks,
> TG

I also have a cutout switch in the generator compartment for the house batteries. You want it nearest the battery so the most amount of wiring is
after the switch.
--
JD Lisenby- USAF Ret
1978 Royale-455
MacDash, Manny Tranny, FI-tech, 3.70 etc etc

Navarre, FL
 
> I don't believe you should EVER run the STARTER current through a cutoff switch. I have never seen a switch capable of the currents (300+ Amps)
> that is required by a starter.
>
> Primary path to starter should be through a starter solenoid relay connected directly to the positive terminal of the battery. The solenoid IS
> capable of
> passing the hundreds of Amps that will be required for starting.
>
> The current to the relay that actuates the starter solenoid SHOULD be supplied via the cutoff switch.
>
> I believe Jim Bounds has schematics of the best way to wire your starter system.
>
> D C "Mac" Macdonald

Mac,

The actual fact is that all the battery disconnect switches available for small (
 
I use one of the battery mounted knife switches on my toad - Honda Fit. Keeps the battery from going flat while under tow. Only minor item - the radio
code must be re-entered after reconnecting the switch, and the clock time reset.
My toad lights are driven by the RV's 12v system.
Tom
--
2012 Phoenix Cruiser model 2552
KA4CSG
 
Tom
I solved that problem several years back by running a wire from my house battery through the light line that plugs into the motorhome and the toad.
I know that puts the toad battery in parallel while you are towing but that hasn’t been a problem.
When you unhook and pull the cable the toad is fully charged.

Emery Stora

>
> I use one of the battery mounted knife switches on my toad - Honda Fit. Keeps the battery from going flat while under tow. Only minor item - the radio
> code must be re-entered after reconnecting the switch, and the clock time reset.
> My toad lights are driven by the RV's 12v system.
> Tom
> --
> 2012 Phoenix Cruiser model 2552
> KA4CSG
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
> Tom
> I solved that problem several years back by running a wire from my house battery through the light line that plugs into the motorhome and the
> toad.
> I know that puts the toad battery in parallel while you are towing but that hasn’t been a problem.
> When you unhook and pull the cable the toad is fully charged.
>
>
> Emery Stora

I was having problems with dead or near dead battery after a day of towing. Emery advised me to run a wire through the electric hookup for lights.
Haven't had a problem since.
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Just FYI, that little cutoff switch Amazon is selling (and I just ordered) is rated for "275 Amps continuous, 455 Amps intermittent, and 1,250 Amps
momentary". That should get it done, IMHO. OTOH, I'm still deciding how I'll wire up mine.

Rick Staples

--
Rick Staples, '75 Eleganza, Johnstown, CO

"Advice is a dangerous gift, even from the Wise to the Wise, and all paths may run ill." -Tolkien
 
I had no idea. that those "little" switches had such capabilities!

Mac. in OKC, OK

Sent from my iPad

>
> Just FYI, that little cutoff switch Amazon is selling (and I just ordered) is rated for "275 Amps continuous, 455 Amps intermittent, and 1,250 Amps
> momentary". That should get it done, IMHO. OTOH, I'm still deciding how I'll wire up mine.
>
> Rick Staples
>
> --
> Rick Staples, '75 Eleganza, Johnstown, CO
>
> "Advice is a dangerous gift, even from the Wise to the Wise, and all paths may run ill." -Tolkien
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Quick n dirty lights pon the toad - my Soul has huge tail light assemblies, so I drilled a hole and added a stop - turn - tail bulb to each. Tow
electrics are completely separate.
As to battery cutoff switches, if the switch is post mounted, opening either one gives the same result. You'd have to short the post to get any
current flow.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
Ok, so got the starting problem fixed. I believe it was a grounding issue. I went back thru and cleaned all the connection with either a brass wire
brush or a brass wheel on my drill. Put it all back together with some lock washer with teeth. Seem to do the job, she cranked right up. This was
out at my storage place so tomorrow I’ll bring it back over to the house and finish all the rest of the electrical clean up and items.

Thanks all for your help!
TG
 
When it comes to those heavy 12 volt cables sometimes you just have to shotgun it and clean all of them. Occasionally is it the starter or solenoid
contacts inside but usually it is the cable connections.

I am happy you fixed it and do not have to worry about them for a few years now.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
I’m glad too. Thanks again for your help. Will finish out on the items you suggested when I get it over here at the house.

Thanks,
TG
 
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