Is this kind of electrical common common?

KompetentKrew

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Hello,

My boat has a set of PROS brand electrical distribution panels, with switches and fuses.

The electrical common is a single stiff wire soldered across all the fuse holders, which I have circled in red in the 3rd and 4th photos below. Has anyone seen an arrangement like this before, please?

The reason I ask is that the common has been cut on one of the three columns of fuses, and I'd like to replace it. I assume the idea was to isolate a couple of circuits - I shall have to investigate further, but these switches are presently without power.

I have thought about replacing this with wire and spade connectors (the local electrical factors sells some narrow enough to fit perfectly), but on reflection I kinda like the way it was done originally. If this is a standard thing, what kind of wire do I need to use replace the common, please? Can I get it from the local electrical factors? I've thought about buying some solid core twin and earth and cannibalising it, but I'm not sure if that would be thick enough. The original looks like it's tinned or nickel plated.

Thanks in advance for any suggestions.

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That is very similar to the system used on my Danish built Nordship 35 from 2000. Is it a Scandinavian thing perhaps?

Yous looks to me like plain copper that has been liberally coated with solder. If it's adequate thickness, I think solid mains cable wire would be OK.
 
It looks like the original fuses were inadequate and some have been replaced. I did one of my switch panels like that and it has been fine for 35 years.
You might find that ETA 3120 thermal breakers might fit in the existing holes and eliminate the fuses.
I'm not too keen on having too many LEDs on when night sailing and prefer the 'Visi rocker' switches for indication like you have.
 
Yes this used to be quite a common common . Do keep an eye on the solder joints though. They can deteriorate.

On a friend's yacht we opened up the switch panel to investigate a dodgy depth sounder, and found that the common wire had come unstuck and was moving freely inside the blobs of solder, only making intermittent contact with them. Had to do some hasty remedial work with some stranded copper wire.
 
It looks like the original fuses were inadequate and some have been replaced. I did one of my switch panels like that and it has been fine for 35 years.
You might find that ETA 3120 thermal breakers might fit in the existing holes and eliminate the fuses.
Yes, I think I have a handful of replacement fuse holders somewhere amongst the boat's spares.

PROS also make faceplates for circuit breakers (magneto-hydraulic ones - I'm not sure the difference), but I'm not sure how much I want to change at present.
 
Is it possible that the bus wire was cut so that the bilge pump could be permanently live when the boat was unattended?
I don't think it's for that. Soon I will start tracing them, and consulting the diagrams I have. A dutch member of the forum previously offered to translate for me.
 
Standard stuff although most people are using breakers rather than fuses these days.

My suggestion would be to review the fuse values and current actually flowing and choose fuse values to suit. Label the panels with fuse values as well as function and have spares well organised in waterproof storage.
 
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