Running the Power to the Electric Head

[deising]

Then it wouldn't be 'exclusive use,' would it?

[LCBrandt]

Now that I think more about it, I realize that there was something wrong in the logic of my previous post.

As previously stated, you certainly need to make sure that the wire gauge used by the macerator is also appropriate for the head. Ideally, the gauge would be sufficient for simultaneous operation of both the macerator and head. But if not, you would have to take care to not use both functions at the same time. Given how infrequently macerating is needed, that shouldn't be too much of an issue to coordinate.

Assuming a simultaneous load that was larger than the wiring could handle, the main macerator circuit breaker should pop, thus protecting the wiring. In no case should you use a smaller-sized wire between your tie-in to the macerator and the head.

Never forget that the purpose of a circuit breaker is To Protect The Boat. It isn't there to protect the equipment loads downstream of it, but rather to keep the wire from burning up the boat in case of a short circuit anywhere along its length.

[ProfDruhot]

Well Larry, I checked the size of wiring to the macerator and it looks like #10. So, I just tapped in to those wires going to the macerator and then place a switch to operate it (the macerator). I also took your advice and wired in two inline fuses; one for the new head and the other for the macerator. It worked pretty slick really and saved me a lot of trouble of trying to tie into the main board. I can't ever imagine using both at the same time so there shouldn't be a problem.