If it's a normal household heater,and there are other appliances in use,the system is being overloaded,if the rcd didn't trip out the hook up point of the pitch would,it's to prevent overheating/fires,try the heater on it's own,you can buy low wattage appliances re kettles toasters fan heaters,I've just bought a 700 Watt halogen heater from Towsure £9.99 very impressed so far
You are overloading it they are ment to trip at 16amps if on a site with 10 amps the site box will keep tripplng..
It is recommended you test on a regular basis by pressing test button which is usually blue for 240volts which trips the main switch. We have to turn tv off if making tea and toast or using micro wave at same time if RDC trips fridge automatically changes to gas operation.
Is the rcd tripping or the mcb? An mcb will trip when the circuit is over loaded and the rcd will trip when there's a fault with an appliance, a short etc. If it's defiantly the rcd then it's a faulty heater.
The OP said it was the RCD that tripped ,RCD's don't trip on overload.
saxo1
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Thanks for the correction,when mine trips,I never look at the name on the switch,I just flick it back up, (your never too old to learn are you) so always assumed it was the RCD switch
RCD is a Residual Current Device which measures the current in the live and neutral conductors. If they do not balance it trips. It should trip at 30mA within 40mS, That's 30 thousandths of an amp within 40 thousandths of a second. That is very sensitive indeed and the vast majority of people should survive touching a bare wire although it is definitely not recommended.
MCB is a Miniature Circuit Breaker which acts in a similar way to a fuse. It will trip if the current exceeds it's rated nominal current by a small amount. There are two modes of operation. On overload (a small amount of excess current) it will trip slowly perhaps after several minutes. On short circuit (a large flow of current) it will trip very quickly within a fraction of a second.
The nominal current is 6A or 10A.
You can get a combined MCB and RCD which is called an RCBO.