flat with one lighting circuit

[AndyPRK]

You have a flat which only has one lighting circuit.
It presently has a consumer unit with fuses.
You are going to upgrade the consumer unit to dual RCD. (or maybe RCBO)

It is not practical to split the lighting circuit into two.

I do not want the flat to be in complete darkness when a bulb blows, (as this causes the MCB to trip).

This is making things less safe from a certain perspective.

How do you stop a bulb blowing, tripping the MCB ?
All options considered.

Would fitting a Type C or D MCB not trip when a bulb blows ?
Surly this would still trip quicker than a fuse ?


Why does an RCBO require an earth connection when an RCD & MCB don't ?


Thanks

 

[hairyben]

Type C's will usually resist lamp-failure shorts, at the expense of dimmers in the circuit.

A flat small enough to have 1 lighting circuit... RCBO's probably no more expensive... How about an emergency light or two, or if cost is an issue a plugin night light in the CU vicinity? Or one of those rechargeable torches that light automatically on mains failure?

 

[SparkyFromTheValley]

impractical it may be, but if losing all lighting is a worry then you may have to use 2 circuits. u can use mains fed emergency lights to come on when the power fails but these are quite large and may be just as impractical.

maybe an emergency light near the CU or in the hallway - you can get decent looking emergency light bulkheads, hav a browse quite a range available.

 

[AndyPRK]

Type C's will usually resist lamp-failure shorts, at the expense of dimmers in the circuit.

Can you please explain why you mention dimmers ?
Do you mean it would allow the dimmer switch to be damaged ?

 

[plugwash]

I would say put the lights on a C6 RCBO and if you are really worried about lack of light fit one or more emergency lights.

As for why dimmers are mentioned it's because dimmers are very vulnerable to surges of current. Using a C6 may make it more likely that the dimmer blows before the breaker trips. Personally I would generally advise avoiding dimmers, having multiple seperately switched lights is a much more sensible soloution to varying lighting level in a room.

 

[hairyben]

Yeah C types allow a larger short current surge that in my experience is more than a dimmer can handle, you could try fitting electronic/intelligent dimmers that are surge-resistant.