Common Ground

[Hellacool]

Installing a second bilge in my 2016 AR240. Is there a common ground in the engine compartment I can tap or do I just need to run a lead to both battery terminals?

 

[Mainah]

There are plenty of "ground" wires in the engine compartment. The issues you will increase the current on whatever path you connect to and will it be big enough for the added current? Think of it like current having to go in a circle starting from the positive of terminal of the battery into the positive side of what you are powering where some gets used before coming out the negative side on its way back to the negative side of the battery and then starting its trip over again aka a circuit. You want the shortest and strongest path possible for the circuit with no weak or choke points. For my float triggered backup bilge I wired the positive to the hot side of the battery switch and the ground to negative terminal of the battery. This is how I would recommend anyone else do it as well.

For those EE types out there yes I know this is not complete nor 100 percent accurate but for the purpose of explaining to a diverse audience I think it is just fine.

 

[Hellacool]

There are plenty of "ground" wires in the engine compartment. The issues you will increase the current on whatever path you connect to and will it be big enough for the added current? Think of it like current having to go in a circle starting from the positive of terminal of the battery into the positive side of what you are powering where some gets used before coming out the negative side on its way back to the negative side of the battery and then starting its trip over again aka a circuit. You want the shortest and strongest path possible for the circuit with no weak or choke points. For my float triggered backup bilge I wired the positive to the hot side of the battery switch and the ground to negative terminal of the battery. This is how I would recommend anyone else do it as well.

For those EE types out there yes I know this is not complete nor 100 percent accurate but for the purpose of explaining to a diverse audience I think it is just fine.

I am not trying to tap a known ground, I was just wondering if there was a ground bar in the bay. A car is easy but a fiber glass boat is a different story.

 

[Mainah]

Exactly no chassis ground in a boat. I am not aware of a ground bar in the engine bay. Best ground in the engine bay for our boats would likey be for the starter.

 

[KXCam22]

Generall you run a ground wire and create a common ground point at the battery. Cam.

 

[itsdgm]

In my boat, each engine block has the largest ground wire going back directly to the battery. On top of that, there's an additional ground strap that connects the engines to each other.

 

[HybridSS]

For future installations you can install a power distribution/fuse block with ground buss. Once installed they really come in handy to hook up various things. You could even install one in a fwd compartment and one in the engine compartment if needed.

Basically run a fused wire from the positive batt terminal to the positive buss terminal on the distribution block. Same with a ground wire but the ground does not need a fuse of course. Once that is done you can then install any accessory, power and ground right to the terminals. Plug in the appropriate rated fuse and your done. I got the Blue Sea 6 terminal set up and just installed it for a subwoofer/amp set up. Still have 5 open circuits for future use.

https://www.amazon.com/gp/product/B000THQ0CQ/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

 

[eticket]

I just installed a second bilge pump and I used a ground terminal block to ease my wiring job. I had too many accessories to ground and the terminal block really cleaned things up.