On 1/10/2018 11:06 AM, Neil N wrote:
> Aviation applications. Of course! Thats great. Thank you.

You bet.  I know it's overkill in a flippin' Vanagon, but it's not that
expensive, and the skills aren't hard to learn.

> ... it looks like they all terminate at the multi
> contact connector at engine block.

Right.  In my Vanagon I installed a ground farm from B&C under the
driver's seat:

http://www.bandc.aero/grounding-supplies-battery-cables.aspx

The big camping battery is inside the sink cabinet, a few inches away
since I drilled a big hole for the heavy + and - cables.  The battery -
cable is connected right to the big bolt on the ground farm.

In homebuilt aircraft, that bolt is intended to go through the firewall
to a ground farm on both sides of the firewall, so there's one ground
point for absolutely everything.  I didn't drill through the van's
floor, but instead grounded the ground farm to the van's body through a
separate short wire.

I run dedicated grounds from each of the 12V outlets to that ground farm.

https://sbw.org/westybattery/

The audio shields are grounded at the radio, and I haven't yet installed
a dedicated ground wire from the radio to the ground farm.  I'd have to
either isolate the radio from the van's frame or run a fairly large
ground wire to close ground loops.  Because I haven't done that, audio
from the cell phone (music, audiobooks, maps), playing through a stereo
cable plugged into the radio, is sometimes noisy when the cell phone is
plugged into the 12V outlet: a classic ground loop.

To eliminate that noise, the easiest way to isolate the radio is to
replace it with a radio that has Bluetooth!  The radio's speaker outputs
are isolated by design, so the speaker wire's shield is grounded to the
radio.

I also installed a fuse farm from B&C under the driver's seat for all
the camping electrics:

http://www.bandc.aero/fuseholder6-slot.aspx

Note that has tabs for spade lugs, which are always better than ring
lugs: Lower parts count (no screws and washers) and a gas-tight
connection with no process sensitivity.  (That is, you can fail to
tighten the screw in a ring lug, or get it cross-threaded, or forget the
washer, or whatever.  None of those mistakes can happen with a spade lug.)