Immersion Heater Wiring

[MarTer]

Hi, I've just obtained an immersion heater & thermostat, 800W, for my calorifier. There were no wiring details & I have a few questions.
1. The element only has two connections, lived & neutral, where should I connect the earth?
2. I have 4 spurs running from the mains junction box each with its own breaker, I plan to connect the immersion heater to the least used spur to the aft cabin. Is this sensible?
3. What is the simplest wiring? I would be happy with a basic on/off switch setup.
4. Anything else I should consider?
TIA

 

[mainmarine]

The fixing post for the cover should have some nuts and washers on it for use as the earth terminal, if not just connect the earth wire to the metal casing, you should have a thermostat as well that is wired in series with the live cable.

 

[rjcoles]

When I wired mine in I used a dedicated 6 Amp mcb in the "RCD consumer unit" and conected to the heater with heat restant cable. This cable only needed to be 1mm2 but I could only find 2.5 cable. I use the mcb switch as the on / off as it is only used occasionally. The earth wire is connected to the screw post inside the head of the heater.

 

[Phoenix of Hamble]

Thats excatly what we do to.... the RCD is the main switch as well as providing its obvious protection

 

[MarTer]

Problem is I have no spare RCDs & the unit is awkward to get to /forums/images/graemlins/frown.gif

 

[mainmarine]

why not connect the least used spur to the MCB feeding the next to least used spur, if the rating is low enough to protect each, then connect the immersion heater to the freed up MCB, or connect the two least used spurs as a ring circuit. You can use a switched spur to fuse and switch the immersion heater