Electrical Install: Buss Bar/Buzzbar material choice

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Turbonic

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A simple question, probably with a complicated answer!

If one were to use pos/neg buss bars in a 12v electrical installation on a boat, are there any issues with using plated brass earth blocks, or is it a case that stainless should be used in a marine environment.

After writing and then re-reading the above I think i've drawn my own conclusion but want to be sure!

Cheers,
Nic.
 
Turbonic said:
A simple question, probably with a complicated answer!

If one were to use pos/neg buss bars in a 12v electrical installation on a boat, are there any issues with using plated brass earth blocks, or is it a case that stainless should be used in a marine environment.

After writing and then re-reading the above I think i've drawn my own conclusion but want to be sure!

Cheers,
Nic.
Click to expand...
No idea of the correct material but ours are stainless.
 
Stainless is often regarded as a poor choice for actual electrical connections.
Plated steel is better, or brass.
Copper is good, but threads tend to strip.
 
Turbonic said:
If one were to use pos/neg buss bars in a 12v electrical installation on a boat, are there any issues with using plated brass earth blocks, or is it a case that stainless should be used in a marine environment.
Click to expand...

No problem with plated brass. Commercial busbars (Blue Sea, etc) are usually tin-plated copper with stainless steel studs.
 
Some good replies above. The fastener material doesn't mater as it's the surface area of the terminal contact with the bus bar that matters most, hence why good quality, commercially available bus bars are usually plated copper with SS fasteners.

There are so many good options "off the shelf" that it really isn't worth making your own unless you have time on your hands (errr - lockdown... ;) ) or need something bespoke. In the case of the latter, I would go with SS for "wet" areas (powerboat engine bays, lazarettes, cockpit lockers, etc) and brass strip for other areas. The limitations of SS as a material choice will hardly be an issue at the loads in those areas and the reliability and performance over time are worth the minor compromises.
 
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Turbonic said:
Sooooo....... Extrapolating a little, I suppose I could use earth blocks?

Example only:

Earth Block 8 Way
Click to expand...


You could, but those are a lesser choice than a bus bar, primarily as there is no bolted connection between the wire and the block. It relies on the integrity of the wire, which in the case of multi-strand is not that high. If you attempt to overcome this by tinning the end of the wire, you create a fatigue point in the wire at the point the tinning returns to multi-strand which will break over time unless well supported.

These were popular, and are OK in certain situations but are not permitted any more for any commercial or class (Type 1) builds.

A much better solution would be a bus bar with mechanical fasteners, and each cable would have a crimped ring terminal so it is through bolted to the bar.
 
Turbonic said:
Sooooo....... Extrapolating a little, I suppose I could use earth blocks?

Example only:

Earth Block 8 Way
Click to expand...

No information there on the materials used, but they are usually nickel plated brass, which is fine in reasonable dry conditions.

If the screws will fully tighten without a wire in the hole you can attach the wires using crimped on ring terminals, if not, use bootlace ferules and put fix in the holes. Do not put bares wires into the holes.

Another drawback is the lack of a bolted connection for the supply cable, but if it's just for a few light current cables behind a panel, it's acceptable. Wouldn't be my first choice though.
 
I would say copper or brass. If its plated all the better. I make my own from brass strip with brass set screws tapped through with ring crimps and brass nuts /washers clamping then down.

I have also used aluminum with brass set screws mainly for my negative bus bar but also for distributed LED lighting connections.

For multi connections like LED lighting I have used HDPE strip with brass setscrews to reduce the number or thin wire going back to my main distribution panel.

All these connection are behind accessible panels for easy maintenance.
 
Rogershaw said:
All these connection are behind accessible panels for easy maintenance.
Click to expand...

Sorry Roger, but this is not the way to do it. They should be fitted into the tightest, most awkward location on the boat, then fit a liner over the top of them, or, at a pinch, build some glued together furniture around them. The object of the exercise is to make it impossible for anyone to access them, if you can route all of the cables in a similar fashion, even better.

This is the modern way of building boats Grrrrrrrr





[insert appropriate number of smileys]
 
A point to note using metal terminal blocks.
I used two, one pos the other neg, mounted on a painted plywood base. I found that there was leakage between the two blocks, so I had to insulate the bottom of the blocks and mounting screws!
I think the paint must have been lead based, it was quite an old offcut.
 
PaulRainbow said:
Sorry Roger, but this is not the way to do it. They should be fitted into the tightest, most awkward location on the boat, then fit a liner over the top of them, or, at a pinch, build some glued together furniture around them. The object of the exercise is to make it impossible for anyone to access them, if you can route all of the cables in a similar fashion, even better.

This is the modern way of building boats Grrrrrrrr





[insert appropriate number of smileys]
Click to expand...


I take you point Paul so all the trunking and conduit and access boxes behind all the LED lighting is also total the wrong way to do the installation.

The great advantage of building your own boat is that you can correctly design the services ( electrics, fresh water, sea water, waste water and hydraulics. so they can be maintained even it it costs a little more in the initial build.

The only issue was I found the 100 x 40 trunking turned out to be too small so I had to bodge it by fitting 100 x 60 trunking and extra 40 x 40 trunking to take extra cabling during the wiring.

Having a steel boat I used magnets to hold the access covers
 
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