Mains/Shore Power AC Cable Size?

Richard10002

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I've done a bit of re-jigging of my shore power and AC wiring as far as the 2 consumer units, (1 from shore power to inverter/charger and spare charger, and the second between the inverter and boat AC system).

Each consumer unit has a 10 Amp and a 6 Amp MCB, so the max it can draw is 16 Amps, (???), and an electrical shop sold me 0.75mm2 cable - I assume this means that each core is 0.75mm2.

Someone has suggested I should have 2.5mm2 cable, which looks a bit of an overkill - but what do I know :)

Is 0.75mm2 OK for up to 16Amps? Do I need 2.5mm2? Or is there a happy medium?

Many Thanks,

Richard
 
I've done a bit of re-jigging of my shore power and AC wiring as far as the 2 consumer units, (1 from shore power to inverter/charger and spare charger, and the second between the inverter and boat AC system).

Each consumer unit has a 10 Amp and a 6 Amp MCB, so the max it can draw is 16 Amps, (???), and an electrical shop sold me 0.75mm2 cable - I assume this means that each core is 0.75mm2.

Someone has suggested I should have 2.5mm2 cable, which looks a bit of an overkill - but what do I know :)

Is 0.75mm2 OK for up to 16Amps? Do I need 2.5mm2? Or is there a happy medium?

Many Thanks,

Richard


To work out the correct cable size you also need to work out the cable length but to my mind 0.75mm2 seems too small. I would use 2.5mm2 but you would probably get away with 1.5mm2.
 
0.75mm² is too small ... It's normally rated 6 amps (Although for short direct connections not bundled with other wiring you'd probably get away with it)

1.5mm² flex is rated at 16 amps.

2.5mm² is rated at 25 amps.

For shore power leads it is normal to use arctic grade cable because it remains flexible at low temperatures .... some of the domestic stuff seems to be only be flexible at normal indoor temperatures
 
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0.75mm² is too small ... It's normally rated 6 amps (Although for short direct connections not bundled with other wiring you'd probably get away with it)

1.5mm² flex is rated at 16 amps.

2.5mm² is rated at 25 amps.

For shore power leads it is normal to use arctic grade cable because it remains flexible at low temperatures .... some of the domestic stuff seems to be only be flexible at normal indoor temperatures


Thanks for that - 2.5mm2 it is then!

My use is indoors on a boat, Arctic seems to come in blue or yellow, and shore leads are often an orange cable of some kind. Is there a difference between the colours?

Which colour should I buy?

I only need a couple of metres, but will probably buy 10 metres and make up a shore power cable with what's left.
 
Which colour should I buy?
I only need a couple of metres, but will probably buy 10 metres and make up a shore power cable with what's left.
Confused now, we thought you were asking about the shore power lead.

For short runs inside the boat 1.5mm² would be OK, but 2.5mm² is better, no need to be Arctic.

For shore power cable, you need Blue Arctic which is normal for 230V, yellow is for 110V. Orange is lawn mower cable!
 
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