Battery to Busbar

Saddletramp

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I am rewiring and need to run a wire from the battery to a positive bus bar. This will feed into 2 fused switch panels and allow for additional switches in the future.

My question is, I want to run as large a wire from the battery as is practical but the bus bar terminals have 6mm studs. What sort of terminals can I use that will fit a 6mm stud and a large (around 8mm dia) wire.
 
A cable of 8mm diameter sounds like 300 amp 40mm square cable. For this you will need a 40mm crimp to M6 ring terminal. The problem is usually buying the tool to fit the terminal to the cable. You also fit heat shrink sleeving to the finished crimp to reduce the chances of short circuits. Marine Electrical can produce such a cable to your requiremnents at a cost of £7.50 plus the cost of the cable. Tel 01248 811677
 
The best range and clearest website I have found is here:

http://www.merlinequipment.com/prod_area.cfm?area_id=37&ind_id=1


If you follow the links you get to pdf's for wire or crimps.

BUT. I would venture that "as large a wire from the battery as is practical" just does not hack it! You need to do some sums and work out what you need with a margin for error and future needs. The PDFs on that site give tables to allow you to work it out. You may be pleasantly surprised, especially if the run is short.
 
I would take a look at this site http://www.merlinequipment.com/ (not sure on how to post the link. I saw them at the boat show recently as I am also doing some new wiring. They have heavy duty leads already made up in various lengths. They also sell a crimp tool for putting lugs on (the type of crimp tool you either have to put in a vice or hit with hammer). I would advise against automomtive equipment if you want the job to last. Also if you can get it buy copper bus bars.
Hope this helps
 
Found a terminal on there that will take 3mm to 7mm wire with a 6.4mm dia hole. Many thanks. /forums/images/graemlins/smile.gif
 
[ QUOTE ]

[BUT. I would venture that "as large a wire from the battery as is practical" just does not hack it! You need to do some sums and work out what you need with a margin for error and future needs.

[/ QUOTE ]

Point taken and I have done the sums, just that I am at work and do not have the info to hand. I will check the data on the Merlin PDF as suggested.

Thanks all.

I shall go to the ball (if i don't fry myself) /forums/images/graemlins/tongue.gif
 
If your cable run is to be 1mtr or more you should use 25mm squared, cable, and 25/6 crimp terminal, which I solder using plumbers solder off a roll.
 
I would suggest that the fuse in the line near the battery is a comment that should be considered carefully.
Yes for the best fire protection you would fit a fuse near he battery rated appropriate to the wire size up to the fuse box.
However you already have exposed battery terminals not fused so you need to make a careful assessment of the risk of the wire from the battery to the fuse box shorting to negative wire or engine or metal structure and of the risk of a red hot wire starting a fire. This risk may be insignificant. If you use a very heavy wire of course the battery may not be able to make the wire red hot anyway. Although the wire may arc to negative starting a fire a situation which a fuse may or may not avert.
You will note that cars have heavy wires not fused to the starter solenoid and often to the fuse box and that in an area with a steel body all around. (much higher risk)

So I am suggesting consider the need for additional fuse at the battery carefully and look at what other manufacturers/ builders do.
good luck olewill
 
[ QUOTE ]
If your cable run is to be 1mtr or more you should use 25mm squared, cable, and 25/6 crimp terminal, which I solder using plumbers solder off a roll.

[/ QUOTE ]
How difficult is this I was contemplating soldering as the leads are in agood dry place, do you end up damaging the PVC insulation a great deal or how do you keep the heat localised, small flame /big flame or practice with a small bit? any help appreciated thanks
 
[ QUOTE ]
You will note that cars have heavy wires not fused to the starter solenoid and often to the fuse box and that in an area with a steel body all around. (much higher risk)

[/ QUOTE ]You can walk away from a car, Will....
 
I've soldered lots of battery terminals using a butane blowtorch and flux. Wet kitchen paper wrapped around the insulation helps minimise damage. Heat-shrink tubing or insulating tape makes a neater appearance.
 
You can buy for £20 a butane powered soldering iron from Maplin. Very good bit of kit as it also has a hot knife, blow torch and hot air attachments. Ideal if you don't have shorepower.
 
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