Getting started

The 240volt wiring system used in Recreational Vehicles differs from households in one very important way: All switches and power points must, by law and for your safety, must be double pole.

What this means is that the switch breaks the circuit of the Active AND the Neutral wires when the switch is set to OFF. In normal household switches and power points, only the Active wire (Red or Brown) is disconnected.

The main reason behind this , is that the RV is connected to the mains power via a 15amp power cord, which can be damaged and repaired by a novice, thereby making it very possible that the Active and neutral wires are reversed. This could be , and has been fatal.

The power supplied to an RV must be delivered by a 15amp power cord. These are identified by a wider than usual earth pin, to prevent substitution with a 10amp power cord. The wire within the 15amp cords is rated higher and allows for the flow of more electricity than a 10amp cord. Modifying a 10amp cord with a 15amp plug should definitely not be done. Even a 'heavy duty 10amp cord' should not be used.

As most Recreational Vehicle owners know, the use of these 15amp cords can be a problem at home, or when visiting friends houses, as most are not able to provide a 15amp power point to connect to. Caravan parks always supply 15amp power points.

The amateurish solution has been to either grind down the earth pin of a 15amp power lead, or replace the plug with a 10amp plug. Both these solutions are preferable, though not legal, to the fitting of a 15amp socket to an existing 10amp extension cord.

There is now a commercial adapter available that will fit a household 10amp outlet, and allow a 15amp extension cord to be connected. This device limits the draw to 10amps to protect the household circuit, but is very useful for keeping the fridge running and using the lights in the RV when visiting friends and relatives houses.

Sample diagram, with related parts for 240v electrics.