blue seas m-Series Mini Selector Battery Switch wiring clarification

[brooksville_rebel]

Hello,
Putting two batteries on the used pontoon we just bought. Purchased the 4 position PN 6007 unit (Off/1/2/Both) and after reading through the forums here. Now I am about ready to install it but little confused on were the grounds go. Been through the forums and seen a couple diagrams but still kinda confused.
I know or think
battery 1 positive to M series 1 lug
Battery 2 posititve to M series 2 lug.
Battery 1 negative to Battery 2 negative.
Motor and accessory panel/fuse box positive to M series Com.

What I don't know is do the negatives from the motor and accessory panel/fuse box go to one or either or both batteries or else were. ?

Now the only wires that were coming to my battery were the positive and negative from the motor and positive and negative from the accessory panel/fuse panel if htat matters.


Thanks
Mark

 

[jhebert]

Re: blue seas m-Series Mini Selector Battery Switch wiring clarification

The switch you have chosen is a single-pole switch, so, of course, only the positive circuit conductors are wired to the switch.

In 12-Volt wiring on a small boat, the battery negative circuit is typically never disconnected by a switch or fuse. The battery negative circuit is the common or reference or ground bus of the electrical installation, and all conductors are wired to a common bus.

I do not recommend that you base your electrical installation on diagrams you find in various on-line forums. There is a very wide range of reliability and experience in those offering recommendations. Your electrical installation should be done to the American Boat and Yacht Council (ABYC) standard, or, at least to federal standards. The ABYC complete standard is available from that organization. You can find segments of it reproduced on-line. Manufacturers of electrical wiring accessories and power distribution components typically provide instructions and wiring diagrams for use of their products. You should prefer those instructions and wiring diagrams to others.

A general description on 12-Volt power distribution on a small boat is given in

Boat Electrical Circuits and Wiring Practices
continuousWave: Whaler: Reference: Boat Wiring

It is critically important that the negative terminals of your two batteries be connected together with a conductor sized for the engine starting current, typically a 4-AWG conductor or larger. If the two batteries' negative terminals are not bonded by a large conductor, you will be at great risk of damage to your electrical system.

 

[Don S]

Re: blue seas m-Series Mini Selector Battery Switch wiring clarification

This picture may be helpful as well.