Ground questions

[Sailing Drummer]

This is really covers a few areas,
1) connections to my hull anode
(2) inverter chassis ground
3) engine block connections.


The boat is a British build from 1990 so when new it came NOT up to ABYC standards. And there have been about 7 previous owners making modifications. Aside from the inverter, there is no other AC power. I took out the original shore power and wiring. Also there is no bonding on any of the through hulls so they are all independent of each other.


I changed my hull anode this year. This is the first time since I've had this boat. Attached to it were wires from:
packing gland
arch (w/ solar)
auto pilot quadrant
inverter (chassis)


It seems to make sense to me that the packing gland and the quadrant are connected to protect them. But the arch has solar panels (12v) grounded to it and the inverter has the chassis ground which I would assume is 120v ground (and I will be upgrading that wire to the appropriate size).


To confuse me more, I've read and I saw on the electrical diagram (from original specs) the engine should also be connected to the anode. But I've also read that there should only be 1 ground for 12v. The engine is the 12v ground through the shaft/prop. The coupling for the shaft is not a flexible one, it's directly bolted so there is a good ground.


So back to my questions.
Should the arch be connected to the engine (terminal block) instead of the anode?
What about the inverter? Is that a 120v ground or is that ground for 12v ? I ask because the inverter has both 12 and 120v. Should that also go to the engine?
Should the engine be connected to the anode?


Thanks,


Larry

[boatbod]

ABYC says the inverter case ground wire should be sized the same or just one size smaller than the dc cables to the inverter. It should go from the case of the inverter to the dc negative bus and protects you in the event of a dc short in the unit.

Solar wiring should not go to your bonding system unless you are simply talking about safety grounding the metal frames of the solar panels.

General principle: keep current flow away from bonding system and your zinc will be happier.

[Sailing Drummer]

Thanks Boatbod. That's what I thought for the inverter. The solar is for the metal frame grounding, not the 12v, so I guess that can stay with the anode. Since the engine grounds the electrical I assume that should not go to the anode?

Larry

[boatbod]

Originally Posted by Sailing Drummer

Thanks Boatbod. That's what I thought for the inverter. The solar is for the metal frame grounding, not the 12v, so I guess that can stay with the anode. Since the engine grounds the electrical I assume that should not go to the anode?

Larry

The engine and shaft probably has it's own zinc so I would keep it separate from the keel if possible.

[Sailing Drummer]

Originally Posted by boatbod

The engine and shaft probably has it's own zinc so I would keep it separate from the keel if possible.

Yes they do. Thanks again.
Larry