M
markc17
Hi all, after some clarifcation really
Carrying out some work in a building, sub divided into Federal electric stablok boards.
All of the ring main circuits in the whole building are protected by 30 amp stablok breakers..type 4.. of which there are hundreds. The conduit is acting at the earting and this is buried floor and ceiling in concrete.
On a recent PIR, some of the EFLI's are coming in 'too high'. It seems that the company that tested have simply used the figures from the regs for a type d 60898 breaker 32 amp - 0.36 and compared it against this.
I cannot find any information on type 4's anywhere so did the calcs (x 50).. and the result is much lower than this and would infact put most of the circuits out.
I did however come across a discussion on a thread, in which somebody said they had the data for a 30A federal 3871 type 4, and that the Zs was 0.64. ( i can only imagine that the lower rated tripping current was used in the calcs)
I am slightly confused, and would love some clarification, and also any information on FE stablok breakers if there is any going...
Many thanks,
Mark
Carrying out some work in a building, sub divided into Federal electric stablok boards.
All of the ring main circuits in the whole building are protected by 30 amp stablok breakers..type 4.. of which there are hundreds. The conduit is acting at the earting and this is buried floor and ceiling in concrete.
On a recent PIR, some of the EFLI's are coming in 'too high'. It seems that the company that tested have simply used the figures from the regs for a type d 60898 breaker 32 amp - 0.36 and compared it against this.
I cannot find any information on type 4's anywhere so did the calcs (x 50).. and the result is much lower than this and would infact put most of the circuits out.
I did however come across a discussion on a thread, in which somebody said they had the data for a 30A federal 3871 type 4, and that the Zs was 0.64. ( i can only imagine that the lower rated tripping current was used in the calcs)
I am slightly confused, and would love some clarification, and also any information on FE stablok breakers if there is any going...
Many thanks,
Mark