What size/type MCB do I need?

[Jango_Fett]

I currently have to install 2 heaters. One heater outside an enclosure which is self heat regulated and one inside the enclosure which will be controlled by a thermostat.

The external heater has a running current of 1A.

The internal heater has a running current of 0.5A, but has a switch on current of 6A for about 1sec. As this will be happening fairly often because of the stat controlling it, I need to spec the MCB accordingly.

Can anyone tell me what size I should use and what type 'B', C or D type MCB?

 

[JohnD]

is this for a fishpond or what?

 

[Jango_Fett]

is this for a fishpond or what?

nope.....just an enclosure with a gas detector in it

 

[briwire]

I would use a 10A type B for that.

You might get away with a 6A type C or D which might withstand the surge you mentioned but it's not worth the mither.