Rewiring mains cabling on board

[mrangry]

Having rewired most of the 12 v dc wiring on board I am now looking at the mains circuits. There is a plug on the stern for accepting a shore power lead, a consumer unit at the chart table, immersion heater in the calorifier and five sockets throughout the boat. My question is, the cabling appears to be yellow flex (American boat), should it not be blue? Or are they the same. I realise blue is indicative of 230 v and yellow 110 v, but are the cables rated the same or should I rewire in blue.

 

[Graham376]

Although you can use whatever colours you want on your own boat, it would make sense to rewire with correct ones, green+yellow for earth, blue for neutral and brown for live. I would use 2.5mm sq. IIRC there's also a maximum distance for siting the consumer unit or breaker from deck socket.

 

[andsarkit]

At 110V the currents will be twice as high so the cables should be more than adequate for 230V use. The biggest problem is that the USA uses black for live and white for neutral which can lead to incorrect connections if you are not aware of this.
Is there anything written on the cables to indicate the size - probably AWG?

 

[mrangry]

At 110V the currents will be twice as high so the cables should be more than adequate for 230V use. The biggest problem is that the USA uses black for live and white for neutral which can lead to incorrect connections if you are not aware of this.
Is there anything written on the cables to indicate the size - probably AWG?

I will check when next aboard and may just buy some arctic 2.5 mm as B&Q stock it.

Is it also advisable to fit a mains isolator switch or simply energise the mains circuits when the plug is inserted?

I also have a Victron 30 a battery smart charger which is mains powered and wonder how best to wire it in, through a switch maybe? If so any recommendations on type?

 

[Graham376]

Is it also advisable to fit a mains isolator switch or simply energise the mains circuits when the plug is inserted?
I also have a Victron 30 a battery smart charger which is mains powered and wonder how best to wire it in, through a switch maybe? If so any recommendations on type?

Your consumer unit should have an isolator switch and an rcd, mine stays switched on so live as soon as shore power plugged in. Mains circuit switches on my boat are standard domestic type, immersion heater switch with neon light for water heater and a 5amp light type switch for battery charger.

 

[Boathook]

I will check when next aboard and may just buy some arctic 2.5 mm as B&Q stock it.

Is it also advisable to fit a mains isolator switch or simply energise the mains circuits when the plug is inserted?

I also have a Victron 30 a battery smart charger which is mains powered and wonder how best to wire it in, through a switch maybe? If so any recommendations on type?

I used ordinary household 3 core flex cable (2.5mm square) when I did mains wiring on board. All protected by a double pole rcd and circuit breakers.

 

[Alex_Blackwood]

At 110V the currents will be twice as high so the cables should be more than adequate for 230V use. The biggest problem is that the USA uses black for live and white for neutral which can lead to incorrect connections if you are not aware of this.
Is there anything written on the cables to indicate the size - probably AWG?

Not quite true. The cable insulation is rated for voltage not current. The cable copper size may be adequate but not the insulation. Colour of the outer sheath is not so important as the cable voltage rating . For 230 volt circuits with flexible cables you should be looking at 400/750 volts. Go to a decent electrical wholesaler and if in doubt they will advise.

 

[PaulRainbow]

Yellow flex does not indicate the cable is American, 110V or anything else much, it might mean it's arctic cable.

The voltage of the cable will be well in excess of what you need (240v), so forget about voltage.

All you're concerned with is current and you should be looking to use 2.5mm cable for the installation you describe. It will almost certainly be 2.5mm already, but check.

If the cable is sound, it's pointless changing it just because it's yellow. If the cores are not UK colours you might want to change it to save confusion, but it isn't essential. I work on lots of boats that have US colour wiring, never a problem.

If you do decide to change it, 2.5mm arctic flex will be fine.