Are multiple earth points allowed?

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pauldowrick

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I have a glass fiber boat that needs a bit of re wiring. Is it acceptable to have 3 earth buses (for'd, mid, and aft) so that the earth cables in each area can be shorter and less hassle to run. Each buss will then be connected via a suitably sized cable to the main bus at the switch panel.
 
pauldowrick said:
I have a glass fiber boat that needs a bit of re wiring. Is it acceptable to have 3 earth buses (for'd, mid, and aft) so that the earth cables in each area can be shorter and less hassle to run. Each buss will then be connected via a suitably sized cable to the main bus at the switch panel.
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12v negative buses, absolutely yes. Make sure the cables going to each one are big enough for all of the loads, allowing for voltage drop.
 
VicS said:
I assume you do mean " negative" rather than "earth".

I'd have thought it was more usual to run twin flex from the distribution ( switch / fuse or circuit breaker) panel to each item.
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Might have been in the 60's, but it's a truly appalling way to wire a boat. I know of no mainstream builder that wires boats this way and i most certainly would not do it.

It's bulky and expensive. If you have 10 things in the forward cabin, why run 20 wires and all of the extra insulation ? Why not 10 positives and a single negative ?

If the equipment in a separate area doesn't need switching from the main panel, why even run separate positives ? Just run a positive (suitably fused) to a secondary fuse/switch panel ? Saves a ton of wiring, time, cost and weight.
 
PaulRainbow said:
Might have been in the 60's, but it's a truly appalling way to wire a boat. I know of no mainstream builder that wires boats this way and i most certainly would not do it.

It's bulky and expensive. If you have 10 things in the forward cabin, why run 20 wires and all of the extra insulation ? Why not 10 positives and a single negative ?

If the equipment in a separate area doesn't need switching from the main panel, why even run separate positives ? Just run a positive (suitably fused) to a secondary fuse/switch panel ? Saves a ton of wiring, time, cost and weight.
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That was exactly my thought. Why run 20 meters of positive and 20 meters of negative when 5 meters of suitably sized negative will do the same thing.
 
PaulRainbow said:
Might have been in the 60's, but it's a truly appalling way to wire a boat. I know of no mainstream builder that wires boats this way and i most certainly would not do it.

It's bulky and expensive. If you have 10 things in the forward cabin, why run 20 wires and all of the extra insulation ? Why not 10 positives and a single negative ?

If the equipment in a separate area doesn't need switching from the main panel, why even run separate positives ? Just run a positive (suitably fused) to a secondary fuse/switch panel ? Saves a ton of wiring, time, cost and weight.
Click to expand...
I have seen on some youtube videos that some circuits have the negative line connected to the engine block if it is close by. Not sure about that one.
 
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