Rcbo for lighting circuit

[ih]

Hi
I have Gewiss Gw40967 split consumer unit which takes B curve mcb Gw 92 xxx
1.All lights in the house are protected with one circuit 6amp mcb
Is it advisable to change the mcb to rcbo? (There is no room in Rcd side of CU)
If so can i put compatible Rcbo ? If advisable then will appreciate if somebody can identify the make.
If Rcbo is advised then will get local sparky to test the necessary.
Thanking in advance

 

[flyingsparks]

Why would you want to fit a rcbo, unless you are adding cables to be buried or have circuits in a bathroom with out supplementary bonding?

 

[stillp]

If so can i put compatible Rcbo ? If advisable then will appreciate if somebody can identify the make.

You should only use MCBs or RCDs from the same manufacturer as the consumer unit.