Electrical safety switches
are a must in every RV wired and connected to 240 VAC. They can and do prevent electrocution and fires.
The correct name for these devices is RCD or Residual Current Device, formally known as an ELCB or Earth Leakage Circuit Breaker.
The purpose of an RCD is to interrupt the incoming 240V in the event of an electrical fault where electrical current flows in the earth circuit. The RCD detects this by measuring a difference in the current flowing in the active and neutral wires.
This can happen due to a faulty appliance or faulty wiring where the wiring has chaffed against the RV's chassis or aluminium frame. This can also happen if you come into contact with the active conductor while also standing on the ground or touching any part of the RV's metallic structure.
An RCD will not trip or provide any protection if you come into contact with both the active and neutral only. Current must flow to ground thereby causing an unbalance in the current flow in the active and neutral wires, to trip the RCD. An RCD is not an over current device in itself.
An RCD can be identified by a 'TEST' button adjacent to the 'ON/OFF' switch which should be activated periodically, usually monthly, to ensure correct operation.
An RCD of the type suitable for use in your RV will trip within 25 mSec when the fault current exceeds 30 mAmps.
Even if your RV does not have an RCD, it will have a main 2 pole circuit breaker, usually 16 Amp. I would strongly suggest that you replace it with a combined 16 Amp MCB (Main Circuit Breaker) / 30 mAmp RCD. This is a special type of RCD, one that functions as an RCD but also incorporates an over current device in the one package.
I would recommend a Clipsal 4EBE 216/30.
(Not the more common and slightly cheaper 4EBEM 216/30)
They are generally only available from an electrical wholesaler and that particular model may have to be ordered in.
The retail cost is around $85 (June 03).
The changeover is literally a 5 minute job but must be done by a qualified electrician.
To see an
enlarged view of this typical circuit below, click on the picture.
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