r1, r2, rn, r1 plus r2 ??

gpz900jim · Mar 7, 2011

When working on a ring main,Instead of working from a cu, which can be awfully crowded with wires, Would it be acceptable to take your r1, your r2 and rn readings and also cross connect your live and cpc in order to get your r1 plus r2 readings by taking a socket off and doing your work from there? Easier and safer ?

i=p/u · Mar 7, 2011

il say from origin as you have to disconnect anyway. how would you know which was which at socket

bugsy · Mar 7, 2011

Should be the same results anywhere on a ring

i=p/u · Mar 7, 2011

and what do i knowwwwwwwwww but suppose would be

tony mc · Mar 7, 2011

Have you seen the NICEIC DVD on PIR testing they use this method especially when you have limited access to the CU.

telectrix · Mar 7, 2011

you have to measure end/end ( r1,r2,rN,) at the CU, but R1+R2 can be done by linking at the CU and measuring from sockets, no problem.

redface · Mar 7, 2011

you can do it from a socket same results what if you are doing a large db with singles and cant turn everythin off and the conductors are not in right place on neutral bar or earth .
the only thing is you need to disconnect for insuletion resistance test because earth to neutral will give a short circuit result
but yes it is recomended for safety to test at socket if you ant switch of

ezzzekiel · Mar 8, 2011

on a old install taking a socket off is usually more trouble than doing it at the board, once you find how short the cables have been cut and the spur thats been added with cores all twisted together.

IQ Electrical · Mar 8, 2011

ezzzekiel said:
on a old install taking a socket off is usually more trouble than doing it at the board, once you find how short the cables have been cut and the spur thats been added with cores all twisted together.

This was exactly the thinking behind using the consumer unit for measuring ring final continuity and cross-connection tests.

At the consumer unit, you can see that all connections are in and tight before you 'lid up' you don't have that 'luxury' as you're pushing back an existing socket with conductors hardened from bending.

gpz900jim · Mar 8, 2011

As you will know, it can be a real pain sometimes, when the wires have not been terminated in their correct places and the wires are jumbled together, and you are standing on a ladder, and its dark, and the cu cant be turned off..... Its useful to know that the ring can be tested from a socket. And its interesting to know that the nic recommend this method when a you have limited access