Radial Circuit Mcb Size

Electrical radial circuit wiring including the size of cable and mcb that should be used.

Radial circuit mcb size. Use a 12 gauge wire for 20 amperes 10 amperes for 30 amperes 8 amperes for 40 amperes and 6 amperes for 50 amperes. Smoke detectors 1 0mm2 radial immersion circuit if you have one 2 5mm2 radial on 16a mcb boiler circuit either spur of the sockets or own circuit 1 0mm2 radial on. Depends what size cable has been used to wire the circuit and the minimum current carrying capacity in any part of the circuit. Hazey7 19 jan 2004.

Hi all i am installing a radial a2 circuit which by rule it should have an mcb of 32amps but when i reference the table 4d1a using reference method a or b current are 26 and 32a respectivitly. I m planning on using 2 5mm twin and earth but wanted to check that this layout is ok and i can put sockets on 2 lines like i have shown. Jan 23 2013. The mcb is run from the main unit in the house with a 20amp mcb although it was only a 10amp when we moved in i d like to add some more sockets and will install a radial circuit.

A 16amp radial circuit with a b16 mcb feeding a 13amp fuse connection unit or socket downstream on a 2 5 mm. A 2 5 t e radial feeding 13a sockets needs to have a 20a breaker. What size mcb 16a or 32a. Wiring a radial circuit in this diy guide you will learn how to wire up a standard radial circuit and also ensure that it is safe by using the correct size of cable and also the correct mcb in the consumer unit.

Cable is a very common circuit in the home think about the immersion heater and the fridge circuits or even the living room heater circuit etc does this mean this common arrangement cannot discriminate well enough. What size wire is needed for a 20 amp 240 volt circuit. 3 sockets on a radial circuit from the consumer unit ie one cable leaving the mcb looped into each socket last socket has one cable only ie not a dual cabled ring main. Reply to is a 16a mcb acceptable for a radial circuit.

The only time this is allowed is if the circuit is wired in 2 5mm pyro. It s a standard circuit arrangement rare in domestic but sometimes used found in the industrial or commercial sectors. In the case of a radial plug circuit the size of the mcb used shall not exceed 16 amps. A radial circuit run with a 2 5 cable should not be supplied off a mcb greater than 20amp even thought 2 5 cable can withstand 26amps or so if the load is greater than this and the mcb is rated at 32 amp the cable can over heat and the breaker still may not trip in time.