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Hello all..
I have a problem with a tripping RCBO and it has me stumped!
Yesterday I fitted 10 RCBO's into a CU which currently had an RCD main switch. This was a sub circuit from a house CU which feeds various circuits for a cattery.
4 of the RCBO's are for the cattery pens. Pens 1,2,3 and 4 (each housing 16 seperate units). Pens 1-3 are 1st fix only (awaiting heat lamps). Pen 4 has heat lamps in.
When any heat lamp in pen 4 is energised the RCBO trips, however if the conductors in the CU for pen 4 are added to the RCBO for Pen 1 all is ok. However, when I IR test between lives of Pen1 and pen4 I get >1000MΩ?
IR tests for pen 4 heat lamps test ok, all >1MΩ.
When I disconnect the neutral fly lead in the CU for Pen 1 I get 197V L-N at Pen 4 and 240V L-E. When I reconnect neutral fly lead for Pen 1 the voltage increases to 240V for Pen 4 so Pen 4 must be utilising the neutral path of Pen 1 but it has >1000MΩ of resistance between neutrals!!
Luckily the cats are not cold at the moment!
Any suggestions would be appreciated :frown:
I have a problem with a tripping RCBO and it has me stumped!
Yesterday I fitted 10 RCBO's into a CU which currently had an RCD main switch. This was a sub circuit from a house CU which feeds various circuits for a cattery.
4 of the RCBO's are for the cattery pens. Pens 1,2,3 and 4 (each housing 16 seperate units). Pens 1-3 are 1st fix only (awaiting heat lamps). Pen 4 has heat lamps in.
When any heat lamp in pen 4 is energised the RCBO trips, however if the conductors in the CU for pen 4 are added to the RCBO for Pen 1 all is ok. However, when I IR test between lives of Pen1 and pen4 I get >1000MΩ?
IR tests for pen 4 heat lamps test ok, all >1MΩ.
When I disconnect the neutral fly lead in the CU for Pen 1 I get 197V L-N at Pen 4 and 240V L-E. When I reconnect neutral fly lead for Pen 1 the voltage increases to 240V for Pen 4 so Pen 4 must be utilising the neutral path of Pen 1 but it has >1000MΩ of resistance between neutrals!!
Luckily the cats are not cold at the moment!
Any suggestions would be appreciated :frown: