by jimmy_one_ball »
Sun Jul 25, 2010 2:05 am
Mr Green
If I understand this correctly then in a word, NO
There is a regulation - 433.4 Overload protection of conductors in parallel - which quotes "Where a single protective device (namely a fuse or MCB) protects two or more conductors in parallel there shall be no branch circuits or devices for isolation or switching in the parallel conductors". I think this concerns your particular requirements.
Also why a 20A MCB?
Use a 6A MCB to protect the switched tier lamps and can't you simply plug the spots into an existing socket outlet? A 3Amp cartrige fuse in the plug top would be suffice.
If this is in the garden as i suspect it is then use RCBO's (unless the circuits are alrady RCD protected). Just use appropriate external cable and you're laughing.
All The Best