Where to ground?

[pjsank]

I want to add a second fuse block to my Series III 109 to run a cigarette lighter plug and a GPS. Since the 109 was converted from 24v to 12v, the wiring is a bit of a hash. Avoiding the primary fuse block seems like the right thing to do. Being a electrical noob is not helping me.:rolleyes:

I have a Blue Sea 5028 fuse block to work with, which does not have a negative bus.

How do I ground the additional devices? To the bulkhead?
If I want Ignition-on power only, what do I connect my Pos+ to?


thanks in advance!

[Jim-ME]

When I put in my extra fuse block I grounded all the extra items to the bulkhead.
Jim

[SafeAirOne]

If I want Ignition-on power only, what do I connect my Pos+ to?

Depends. What series/year?

[pjsank]

Depends. What series/year?

82 SIII 109. Neg Earth

[antichrist]

I'm fond of the Blue Sea covered fuse blocks. The 5025 would do you.
http://www.powerwerx.com/_images/products/BS5025_drawing.jpg

They're available with 6 or 12 circuits and with a ground buss.
Then a fused circuit from the battery to the fuse block, and a common ground from the fuse block to where your battery grounds.

[SafeAirOne]

82 SIII 109. Neg Earth

In that case, I'd run it off either the post where the white wire connects to the ignition switch or where the other end of that white wire connects to the existing fuse panel.

Also, if I was running a bunch of electrical stuff off the new fuse box IN ADDITION to the existing equipment fed off the 'hot-in-run' side of the existing fuse panel, I would probably supply power to the new fuse box through a relay that was activated by the power to the previously mentioned white wire.

Of course, this depends on what your master plan is and whether you are simply replacing the existing joke of a fuse box or whether you're adding on an anti-aircraft searchlight, a toaster and steam iron to the existing electrical system.