S
sambuca2907
Could I pick someone's brains with this - as I've been scratching my head trying to think about it!
I've got a 25 metre 2.5 SWA run to a garage, running 2 double 13A sockets as a radial. Protected by a 20A MCB on an RCD (17th regs compliant), located in the house CU.
Customer asked me to re-do the lights in the garage - and to save running a new supply I've put in a 5A spur from the garage radial (BEFORE the sockets).
From this I've got 2 way switching - in 1mm 3&Earth,
and 2 F.L. Tubes, ran in 1.5mm T&E.
Gone to test the install - and got an R1 + R2 at the furthest light at 2.03 Ohms! Thought this was really high so checked all connections and re-tested - same result... Checked the R1 + R2 at the sockets and got around 0.65 Ohms - much more realistic figure! Is this just simply because of the amounts of 1mm and 1.5mm I've used in the 2-way lighting?? When I obtained the figure I disconnected the F.L. Lights, just incase they were effecting the result.
With the Ze being 0.14 Ohms, this makes the Zs 2.17. However the circuit is protected by RCD - and the RCD trip times are within limits (34.8 ms @ I and 12.5ms @ 5I)
I've got a 25 metre 2.5 SWA run to a garage, running 2 double 13A sockets as a radial. Protected by a 20A MCB on an RCD (17th regs compliant), located in the house CU.
Customer asked me to re-do the lights in the garage - and to save running a new supply I've put in a 5A spur from the garage radial (BEFORE the sockets).
From this I've got 2 way switching - in 1mm 3&Earth,
and 2 F.L. Tubes, ran in 1.5mm T&E.
Gone to test the install - and got an R1 + R2 at the furthest light at 2.03 Ohms! Thought this was really high so checked all connections and re-tested - same result... Checked the R1 + R2 at the sockets and got around 0.65 Ohms - much more realistic figure! Is this just simply because of the amounts of 1mm and 1.5mm I've used in the 2-way lighting?? When I obtained the figure I disconnected the F.L. Lights, just incase they were effecting the result.
With the Ze being 0.14 Ohms, this makes the Zs 2.17. However the circuit is protected by RCD - and the RCD trip times are within limits (34.8 ms @ I and 12.5ms @ 5I)
