Impaler
Well-Known Member
I want to instal a house battery and would like to know what size wire I should use. All help gratefully accepted.
What size electric wire?
- Thread starter Impaler
- Start date
LadyInBed
Well-Known Member
From where to where?
Battery to 1 Both 2 switch - BIG
Battery to Alternator - BIG
1 Both 2 switch to distribution box - BIGish
Battery to 1 Both 2 switch - BIG
Battery to Alternator - BIG
1 Both 2 switch to distribution box - BIGish
sarabande
Well-Known Member
which wires do you want ?
charger to battery,
alternator to battery
battery to distribution bar
battery to meters
battery to other batteries
battery to instruments
battery to lights
charger to battery,
alternator to battery
battery to distribution bar
battery to meters
battery to other batteries
battery to instruments
battery to lights
Impaler
Well-Known Member
I need to join the house & starters negatives.
House battery to isolator switch and isolator to switch panel for lights etc.
And then tie in the VSR between the 2 isolator switches if that makes sense.
All the starting wiring is in position and I shouldn't need to change that. I hope.
House battery to isolator switch and isolator to switch panel for lights etc.
And then tie in the VSR between the 2 isolator switches if that makes sense.
All the starting wiring is in position and I shouldn't need to change that. I hope.
saltwater_gypsy
Well-Known Member
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It depends of course on the current draw you intend to make. Add up the current consumption of all the equipment and then make a selection. As a guide , here is a rating list for single core PVC coated wire
source--Lucas Marine)
Cross section (square mm)---- Amps
1------------------------------- 13
2.5-------------------------------24
4---------------------------------32
6---------------------------------41
10--------------------------------57
These are maximum ratings and you must also cosider the possibility of voltage drop over long cable runs. I would suggest that you take 10squ.mm from the battery to a distribution or swtchboard and use lighter cable to each appliance.
Lastly you may want to consider having rhe domestic battery as backup to the starter battery in which case you should use the same cross section as the starter cables to a two way switch.
Check the Forum for previous posts on this subject---it is quite common
source--Lucas Marine)Cross section (square mm)---- Amps
1------------------------------- 13
2.5-------------------------------24
4---------------------------------32
6---------------------------------41
10--------------------------------57
These are maximum ratings and you must also cosider the possibility of voltage drop over long cable runs. I would suggest that you take 10squ.mm from the battery to a distribution or swtchboard and use lighter cable to each appliance.
Lastly you may want to consider having rhe domestic battery as backup to the starter battery in which case you should use the same cross section as the starter cables to a two way switch.
Check the Forum for previous posts on this subject---it is quite common
pappaecho
Well-Known Member
You will find that electrical suppliers supply multistrand "meter tails". which are used to connect meters to the main fusebox.
Good for 120 amps, this stuff is double insulated, and the inner layer is coded either red or black. This stuff is sold cheaply by the metre, and is very good for constructing a sub mains system to take all the power from the non engine scenario, lights, navigation aids, bilge pumps, fridge etc. If you are renewing internal wiring to each cabin you also might like to consider "colour coded 12 way cable" used in wiring lorry chassis, as this is good for 16 amps max per pair, and again is double insulated, and in my case we used one 12 way cable for each cabin, and one specifically for the lighting, bow, masthead, spreaders and stern light
Good for 120 amps, this stuff is double insulated, and the inner layer is coded either red or black. This stuff is sold cheaply by the metre, and is very good for constructing a sub mains system to take all the power from the non engine scenario, lights, navigation aids, bilge pumps, fridge etc. If you are renewing internal wiring to each cabin you also might like to consider "colour coded 12 way cable" used in wiring lorry chassis, as this is good for 16 amps max per pair, and again is double insulated, and in my case we used one 12 way cable for each cabin, and one specifically for the lighting, bow, masthead, spreaders and stern light
William_H
Well-Known Member
Inevitably one day you wilol want to use the house battery to boost the start of your engine battery. So especially for the connection of negatives you need to use heavy wi9re for hundreds of amps. ie just like the start battery to starter wire.
Depending on how you will get this jump start you need to provide heavy wiring to the jump connection. ie to the switch that will provide the boost.
That is unless you will use a separate jump cable for the positive. ( a dangerous thing to do due to possible sparking and subsequent explosion)
Best IMHO is a heavy wire to a heavy switch remote from the batteries by a meter or so)
The rest of the wiring should be good for 30 amps to provide for fast charging of a low house battery. good luck olewill
Depending on how you will get this jump start you need to provide heavy wiring to the jump connection. ie to the switch that will provide the boost.
That is unless you will use a separate jump cable for the positive. ( a dangerous thing to do due to possible sparking and subsequent explosion)
Best IMHO is a heavy wire to a heavy switch remote from the batteries by a meter or so)
The rest of the wiring should be good for 30 amps to provide for fast charging of a low house battery. good luck olewill
Impaler
Well-Known Member
Many thanks, more or less what I thought.
