marine grade electrical wire

I'm also considering this approach, but already have 2 complementary switch pannels so think 3 core would provide the best result.

Tricolour/Anchor - 3 core
Steaming/Deck - 3 core

Thinks I'll replace the masthead ariel while the masts down this winter as well... don't plan on dropping the mast for another 3 years :-)
 
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My boat was re-wired by the previous owner. Heavy solid copper 2 core, the stuff you'd use in your house for mains sockets - bends & stays in that position.

Am getting lights dimmining/flickering and investigation shows these wires are BLACK.

I'm thinking or replacing with the tinned stuff internally to cater for damp condensation between inner/outer mould and improve the power transfer across all lights on the loom.

Overkill???

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That's your problem. With the inherent vibration and flexing you get on a yacht, solid copper domestic cable will break.

You require FLEXIBLE cable, and as I said earlier, coating the connections in silicone grease or spray to keep the moisture out will reduce the likelihood of problems developing.
 
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are you aware that you can get away with using a single pair, a set of switching diodes (many LED light 'bulbs' have enough reverse polarity protection that you don't need additional diodes if you've gone that route), and a DPDT centre-off switch?

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I'm not sure if your are an electronics engineer or not as you call yourself a business man in your profile.

The idea of two LED lights eg tri and all-round white wired with opposite polarities on a just a twin core cable and controlled with a DPDT switch is quite a smart one.
(provided they will stand the full 12 volts reverse polarity)
You would perhaps have to watch out for any deck plugs in which one conductor is connected to the outer metal casing, but I think that only applies the three pin ones. Otherwise sounds a smart idea but unless one is fitting LED lights anyway it would push the cost up. The low current requirements of the LEDS means that much lighter cable can be used as well as saving one core but it would be a pretty light weight boat for the weight saving aloft to be significant.

The use of diodes in conjunction with conventional bulbs to utilise the same clever switching is not so attractive because one is always conscious of voltage drop on long cable runs such as to the mast head. The diodes would immediately impose a 0.6volt drop wouldn't they?
 
NAJS

Have not got time to look it up tonight, but I think the boat safety scheme advises multi core wiring. This is because of the risk of fatigue cracks forming from vibration.

Philip
 
Well, if it is good enough for oil rigs, it's good enough for my boat /forums/images/graemlins/smile.gif

They make this cable properly, so it will last for longer than the boat, the fact that this is one characteristic of its performance is neither here or there. Most of the wiring on my boat was done when I bought it, and it is NOT tinned-copper. Every piece fitted by me is. What you or others do is your decision. I am sure we have some really cheapo stuff I could recommend to you.... /forums/images/graemlins/tongue.gif
 
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You reference '3 core stuff' for your nav lights. If this is for a tri-colour/anchor light combo, are you aware that you can get away with using a single pair, a set of switching diodes (many LED light 'bulbs' have enough reverse polarity protection that you don't need additional diodes if you've gone that route), and a DPDT centre-off switch?


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OK, I'm intrigued. How do you do this then ?
 
Not disagreing with you in any way, and you're probably right in that it will last longer than your boat.

All I was questioning is, do you REALLY require something with such a high spec?
 
To Vic and Bob,

I have a drawing of the circuit, but not on this computer (it's 0530 local!). Later today I'll pull it off the one in the office and start a fresh thread. I've been 'going to get around to' putting up a page on our site of how to do it, now's as good a time as any, I suppose.

Ordinary silicone will have a ~0.7 voltage drop, shottky diodes will take the drop to less than half of that, ~0.3v, and so can be used with any pair of lights. You do need to keep an eye on the current ratings of the diodes. A good rule of thumb is to allow for a 100% safety margin. Often, it's cheaper to run two or more diodes in paralel to get the current instead of buying a single 'monster' diode.

Best regards,
Michael
 
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