Battery Disconnect

I use the 250A switch for race cars. Never had any issues. Some on the + and some on the - depending on the wiring setup. I always took the simple route. Mounted them on the exterior in a weathertight box so I can access them without opening a compartment door. You could say I'm lazy but it's simple.

beemerphile1 wrote:
You are good to go.
Breakaway to positive terminal of batteries.
Heavy, heavy cable from batteries positive to switch.
All other positive lines to load side of switch.

Thanks*

You are good to go.
Breakaway to positive terminal of batteries.
Heavy, heavy cable from batteries positive to switch.
All other positive lines to load side of switch.

For redundancy sake, i'm going to revisit this topic one more time in all my procrastination.

I am going to get another 12v battery friday. It's not an exact match, but only 2-3 weeks old, and it will be a matching brand from the dealer that installed the original when we bought the TT.

I'll be running parallel.

My switch is 100A continous, and 1000 surge. Other than my breakaway, i want to hook 1 wire from battery to switch, then 3 wires from switch to their destination.

I want to do this on the POS. terminal, for no other reason than because the consensus is 50/50.

I'm good to go, or does someone for see a problem in my logic?

I don't know what you are putting the switch into. If it is a trailer the switch must be on the positive and the breakaway switch is wired directly to the battery prior to the switch. It is inevitable that someone, somehow, somewhere will tow with the switch off.

There is no way to wire the breakaway switch around it if installed in the ground line.

thirtydaZe wrote:
... can i just place all the cables onto 1 end of the disconnect, and then wire a single hot wire from battery to the other end of the switch?

As others have said; What you are proposing is fine... as long as you don't exceed the switch's continuous current rating.

I have a similar switch (shown just above 115Vac outlet in photo below) that is manufactured by Hella and it is rated at 50A continuous and 1000A for 10 seconds. I use it to disconnect the positive cable between my chassis & coach batteries. Mine sees 40A continuous and 100A for a minute or two, and has been trouble free.

I'll add that I go through some effort to avoid opening or closing my battery disconnects under load. This prevents arcing and pitting of the contacts... something to consider if you have any high-current accessories (e.g. inverter) in your system.



Cheers,
-Mark

that blue sea switch does look like a nicer unit.

I went thru 2 of those switches in one summer. Rain got in and corroded the contacts. Replaced with a Blue Sea switch.

thirtydaZe wrote:
Well, i went out and took a solid look at things, my positive post has 4 wires, two 6 gauge, and two smaller wires, im guess 10 or 12 gauge.

My negative post has only two 6 gauge wires, so im guessing a lot of wires groundng to the frame.

Best bet to isolate what one of my positive cables is the main power and just put the disconnect on that alone?

If you want to completely isolate the batts from all draws, you need to know which wires carry what. As said above, some things don't draw unless you use them, like the slide or jacks. Other things like the LP alarm/stereo clock by- pass the usual battery disconnect.

So just collect those wires that you need to be off and ignore the ones that are off anyway.

Good point mentioned above about your break-away brake switch.

Note that your Trimetric if you have one will draw too just to keep its lighted numbers on, unless you isolate its pos terminal. (or you could undo its fuse on its pos line) Means a reset for every trip if that matters to you at all (doesn't matter the way I use the Trimetric)

My main use of the battery disconnect is when charging from a portable charger. I disconnect the batts and run the rig 12v from the converter (poor at charging) while the portable charges the batts with no draw on them from the rig. In that case I only need to have the switch on the main wire (either neg or pos) to the rig's converter/DC panel.

Current in equals current out. Neither one has more draw. Pick your favorite.

Jim