VOLTAGE OPERATED ELCB BE842

StuartBa:

Basically the elcb is to be removed as its type Bs842 no longer confirms to regulations. I am removing the old wylex fuse board and replacing it with a new CU with individual rcbo's. My question was rather than remove the obsolete elcb could I use it as an isolator switch 

BS 842 is not listed in Table 537.4, and therefore it's not easy to determine whether the device complies with Regulation Group 537.2 in the 18th Edition. One particular issue is that BS 842 doesn't explicitly state that the device is suitable for isolation, but this could perhaps be inferred by other wording in the standard, and it requiring the ELCB also complies with other product standards that may be suitable for isolation (but also are not listed in the current 18th Edition for that purpose).


However, I do know that a BS 824 device is only specified for prospective fault currents of 3 kA (if working to the standard - although I guess a particular manufacturer may have chosen a higher rating). If the supply has been upgraded from its original demand in the past, or will be in the future, that rating could be exceeded. (See ENA Engineering Recommendation P25 for further information - it's common these days, to simplify designs and purchasing requirements consumer units and associated equipment, to assume single-phase installations up to 100 A might be subject to 16 kA prospective short circuit currents.)

StuartBa:

Basically the elcb is to be removed as its type Bs842 no longer confirms to regulations. I am removing the old wylex fuse board and replacing it with a new CU with individual rcbo's. My question was rather than remove the obsolete elcb could I use it as an isolator switch 

BS 842 is not listed in Table 537.4, and therefore it's not easy to determine whether the device complies with Regulation Group 537.2 in the 18th Edition. One particular issue is that BS 842 doesn't explicitly state that the device is suitable for isolation, but this could perhaps be inferred by other wording in the standard, and it requiring the ELCB also complies with other product standards that may be suitable for isolation (but also are not listed in the current 18th Edition for that purpose).


However, I do know that a BS 824 device is only specified for prospective fault currents of 3 kA (if working to the standard - although I guess a particular manufacturer may have chosen a higher rating). If the supply has been upgraded from its original demand in the past, or will be in the future, that rating could be exceeded. (See ENA Engineering Recommendation P25 for further information - it's common these days, to simplify designs and purchasing requirements consumer units and associated equipment, to assume single-phase installations up to 100 A might be subject to 16 kA prospective short circuit currents.)