British General Fortress 16A 2-Pole Digital 2-Channel Consumer Unit Timer Module (4238P)

Wiring diagram for 2.channel timer for lighting

Hi Retneprac12, They are Normally Closet terminals to allow for devices or circuits which require this, or to allow for switching between circuits or use in a 2-way circuit as with any normal 2-way light switch.

Hi Retneprac12, The timer consumption is so low that it could easily be fed from any convenient breaker in teh consumer unit, the only reason it has a separate supply is to allow for it to be powered from a different circuit to the two output channels if necessary.

Hi Retneprac12, Yes, the timer function has a separate supply connection to each of the channel connections, so there is L and N on the right for the timer function, then channel one has terminals 1, 2, and 3 with 2 being the input L and 1 being the output SL, channel two has terminals 4, 5 and 6 with 5 being input L and 4 being the output SL. This layout allows for separate breakers to be feeding each of the 16A rated switch mechanisms, and a third running the timer function.

Hi Nickstay, As long as you do not overload either channel (16A / 3840W resistive, 10A / 2400W inductive each) then it doesn't particularly make any difference what you are actually controlling.