Battery Switch com terminal too large to hook up all accessories

[dmlinn]

Hey guys, boat newby here, i have a 2002 monterey LS218, 5.7 mercruiser, alpa one outdrive, BEP 721 battery switch. Two Exide marine batteries, one starter 1000 CCA, and one deep cycle 730 CCA. Right now helm wiring, trim pump wiring, and stereo amplifier is wired directly to the 2nd deep cycle batt. I'd like to wire everything to the com terminal on the switch, but it is too large diameter to accept the smaller wire connections. Can you wire a bus bar to the Com terminal to accommodate all the accessory wiring?

 

[UncleWillie]

Re: Battery Switch com terminal too large to hook up all accessories

I would leave the Miscellaneous connections on the House (Deep Cycle) Battery.

The Start Battery is For Starting ONLY.
Don't use it to operate the radio or you might not be going home anytime soon.

You are a candidate for an ACR.

 

[Auger01]

Re: Battery Switch com terminal too large to hook up all accessories

Hey guys, boat newby here, i have a 2002 monterey LS218, 5.7 mercruiser, alpa one outdrive, BEP 721 battery switch. Two Exide marine batteries, one starter 1000 CCA, and one deep cycle 730 CCA. Right now helm wiring, trim pump wiring, and stereo amplifier is wired directly to the 2nd deep cycle batt. I'd like to wire everything to the com terminal on the switch, but it is too large diameter to accept the smaller wire connections. Can you wire a bus bar to the Com terminal to accommodate all the accessory wiring?

Yes, you can do that. You could also put larger ring terminals on the smaller wire to fit the switch. GenuineDealz.com - Marine Electrical, Boat Wire & Cable, Custom Battery Cables sells good heat shrink ring terminals of all sizes at a great price. If you have more than three or four small wires to connect, the bus bar would be a better option.

Are you planning to switch to the start battery for running, then switch to the deep cycle at the destination, then switch back to the start battery for the ride back to the dock? That is a lot of switching.

 

[Don S]

Re: Battery Switch com terminal too large to hook up all accessories

Best thing to do is hook up a single wire from your battery switch common terminal to a bus bar. Then hook all your smaller fused wires to it.

A small bus bar like this. Minibus 100 Ampere Common Bus, 5 X 8-32 - Blue Sea Systems 2304 - iboats

Since it's positive, use the cover too Cover for MiniBus 2304 and 2305 - Blue Sea Systems 2713 - iboats

 

[jhebert]

Re: Battery Switch com terminal too large to hook up all accessories

It is not a good practice to have more than one terminal connector under any fastener or binding post, and that is why bus bar wiring accessories are sold. While aggregating two ring terminal connectors under one fastener is sometimes done, you should never expand this bad practice; get the appropriate wiring accessories to distribute electrical power properly. You should never use a switch terminal as a wiring point for multiple connections. If you need to daisy-chain a circuit among several switches, join the two conductors at the terminal connector, that is, crimp them into one terminal connector.

 

[UncleWillie]

Re: Battery Switch com terminal too large to hook up all accessories

Are you planning to switch to the start battery for running, then switch to the deep cycle at the destination, then switch back to the start battery for the ride back to the dock? That is a lot of switching.

Switch to the Start Battery for Starting.
Switch to BOTH for running.
Switch to the Deep Cycle at the destination.
Switch to the Start Battery for Re-Starting.
Switch to BOTH for running back to the Dock.

Now That's a lot of switching! Don't mess it up!

 

[Don S]

Re: Battery Switch com terminal too large to hook up all accessories

Switch to the Start Battery for Starting.
Switch to BOTH for running.
Switch to the Deep Cycle at the destination.
Switch to the Start Battery for Re-Starting.
Switch to BOTH for running back to the Dock.

Now That's a lot of switching! Don't mess it up!

LOL. With an ACR, the steps go like this.

1. turn switch on at start of trip.
2. turn switch off at end of trip.

Let the ACR and Switch do all the work and keep thing separate.

 

[NYBo]

Re: Battery Switch com terminal too large to hook up all accessories

It is not a good practice to have more than one terminal connector under any fastener or binding post, and that is why bus bar wiring accessories are sold.

I remember reading somewhere the maximum acceptable number of connectors being four. I have a feeling that most of us break your recommendation.

 

[Auger01]

Re: Battery Switch com terminal too large to hook up all accessories

I remember reading somewhere the maximum acceptable number of connectors being four. I have a feeling that most of us break your recommendation.

Four is the accepted maximum for for aircraft. Granted, boats don't fly, but I still believe it to be a good guideline for marine applications.

 

[dmlinn]

Re: Battery Switch com terminal too large to hook up all accessories

Thanks to all for the advice, there is a wealth of information and experience here on these forums. I think adding the ACR and the bus bar would be the way to go. That way I can clean up all the wires, and not have to worry about switching batteries all the time. Thanks again to all who replied.