WHAT IS AN RCD ?

RCD stands for Residual Current Detector (or Device) and is also
known in England as an Earth Leakage Circuit Breaker or ELCB.
In the US is referred to as a Ground Fault Circuit Interrupter (GFCI).
It's hebrew name is  'Memsar Pechat'

It's function is very simple and very effective.  It sits on the
main fuse panel and continually compares the current
entering the house with that leaving it.
A small discrepancy between the two , results in the immediate
cessation of power.

 ISN'T IT REALLY A BIG FUSE ?

No.  A fuse or normal circuit breaker blows when there is a short
or an overload.  The RCD 'trips' on leakage to ground.

 WHEN DOES IT TRIP ?

When little James sticks his finger into the power outlet, or the
washing machine spills water over it's motor, or the boiler springs
a leak near the element, or ....

WHAT DO YOU DO WHEN IT TRIPS ?

Firstly ensure that no-one still has his finger in the outlet and
then depending on the type, either gently lift up the little
lever or push in the large button.
If it stays on then ok (probably a transient problem), but if it
immediately falls again, put down all the circuit breakers except for
the main one and try again to reactivate the RCD.

If the RCD still fails with all the breakers down, call an electrician.

If the RCD  can  be re-armed , lift each circuit breaker separately until
you find the culprit.

Pull out (disconnect) all the appliances and switch off all the lights
on that circuit.   Try now to raise the circuit breaker.  If it still
causes the RCD to trip, call an electrician.
If it goes up ok without tripping the RCD, go around plugging back
all the appliances one by one and switching on all the associated lights
until you find the culprit.
If the problem is with an appliance such as a fridge or washing machine
and there is no obvious reason (like a wet or damaged plug or socket),
then you should call an approved appliance technician.
 

 HOW CAN I KNOW IF THE RCD IS WORKING ?

Although it takes specialised equipment to do a complete test of
the device, you can do a basic test by pressing the button marked
T or Test .  Ensure that this causes the RCD to trip IMMEDIATELY
without the slightest delay.  (It should actually take a mere 25 msecs)
Do this test every month or two.
 

WILL THE RCD PREVENT ME GETTING A SHOCK ?

It depends on your sensitivity to electric shocks , but the device
is set to trip at a level that should not cause physiological damage.

We can supply and install a special RCD that will trip at much lower
levels of shock.  This device is ideal for localised use in
children's or old person's rooms.
It's not recommended for covering the whole house as it's much
more likely to be tripped spuriously and become a nuisance.

HOW LONG SHOULD THE RCD LAST ?

It all depends on the use ..  and misuse.  Every RCD has a maximum load
current.  Exceeding this can cause the device to wear out quicker.
Continually tripping it or overloading the main circuit breaker can
hasten it's demise.  Water is another enemy.

Most RCD's carry a 1 year warranty against faulty manufacture but
they usually go on functioning properly for 5 years and more.
 
 

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 An information sheet from        EDS  CONSULTANT ELECTRICAL ENGINEERS
                                                                    AND LICENCED ELECTRICIANS
                                                                                   Tel:  02 678 1627