Why would you use this??

[C&GStudent]

Greetings All!

Why would you use this in a consumer unit rather than a MCB?

 

[dingbat]

Lights.

 

[Nige F]

My hager board had these -and of course larger A. ones for power..............one blew and so did I when i had to buy a new fuse I changed them for mcb`s .before part P of course as I`m not an electrician

 

[JohnD]

cheap. In most installations most fuses never blow in the whole life of the installation.

MEM fuseholders have a compartment for holding a spare cartridge, which is a terrific idea.

 

[kai]

A way round the Blown Bulb tripping MCB problem, is to wire a 2.5.mm ring final circuit on a B32 around the whole house, feed the lights in each room off a fused spur with a 5 amp fuse in it, and have no sockets, just the FCU's on the ring, a safe and workable method.

 

[RF Lighting]

Surely a type C MCB would be far easier, and a lot more conventional.

 

[Adam_151]

Conventional and kai have never gone together for as long as I have been a member of this forum

 

[Adam_151]

@the OP, I imagine if the PFC tends to the high side, then one of these might keep the I²t down more than a breaker (might be usful if for example you are trying to make a 2.5/1 ring comply). Also I expect that if the CU is in less than favourable conditions, eg greasy kitchen, there is a chance that grease might get in ad jam a breaker (or make it operate ore slowly), a fuse however is more a less immune to such things

 

[ban-all-sheds]

Conventional and kai have never gone together for as long as I have been a member of this forum

Plus he can carry spare fuses in his pockets without needing them to be double-reinforced.

 

[Lectrician]

MCB's used to be twice the price of the HRC - not so now.

Bulbs tripping MCB's is a problem, but they are increasingly also fusing fuses. I have seen a 3036 go a couple times.

C type them if you must - or just get used to the fact this is now a common occurance - since they started to cheaply manufacture the lamps by missing out the internal fuse designed to fuse when the lamp fails.

 

[Spark123]

Fuses can have a 5s disconnection when used for fixed wiring hence the max efli can be higher than its MCB cousin whos max efli needs to be low enough for a 0.1s disconnection.

 

[ricicle]

Spark123,
Fixed installations can have a max disconnection time of 5s regardless of being protected by fuse or mcb.
Or is that what you were trying to say!

Ricicle

 

[Spark123]

I was referring to the figures for MCBs in appendix 3 of bs7671 where there is only one value of current given for each MCB which is the same for 0.1s to 5s disconnection.
For fuses there are different values of current for different disconnection times, hence the maximum efli for a fuse can vary depending on the required disconnection time.

 

[ricicle]

My apologies.I see what you were saying.

ricicle