Mims

[nickblake]

Right chaps had a spooky one to day ,Periodic inspection of a church ,complete with coffin ,(funeral later in the day ) right refused to carry out some of the tests due to the respect value , but heres the crunch mims metal clad DB mims in mims out top and bottom all sockets metal clad mims in , installation is 55 years old but testing out ok , as youd expect with pyro , problem is the ring main L N continuity fine 0.48 on each , but its a metal clad DB and metal Clad back boxes and only an inch of exposed pyro so and cpc readings will be incorrect , so i have dont 2 R1 R2 tests and measured from the furthest points , insulation reading were >200 M so no probs any thoughts

 

[oldtimer]

Because there is metal back boxes and metal DBs and it is 50 odd years old then it falls under the 14th edition ie electrically & mechanically sound principle as for the testing I am not sure about the inch of exposed pyro ? Have you tried testing just using the metal of the box as your earth ? me thinks you will have to highlight this on you sheets to indicate that the earth is the sheath of the pyro

 

[nickblake]

yes i agree all tests out fine the integrety is very good the inch of pyro is whats exposed at the CDU and sockets its been dry lined over it , its on the cert as cpc mims and also ltd on cpc but appart from that in very good condition

 

[IQ Electrical]

In this situation, you can use an R2 wander lead to each socket outlet and just record the highest reading in the R2 column on the schedule of test results, an R1+R2 test would be meaningless.

It doesn't matter what edition of the regulations an installation was installed under, a PIR compares it to the current edition.