What’s going on with this radial

[John tomo 1972]

Called to a property which has just been sold to do an EICR
The sockets down stairs including the kitchen were on a 16a 2.5 radial the issue being the Zs for the first couple of sockets were about average readings but the last few and the sockets in the kitchen went from 0.90 ohms to 1.19 ohms. Personally I wouldn’t put a kitchen on a radial but that’s just my preference. But why the higher than normal results could it be a case of more than one spur from a socket That’s giving me high readings also 16a is just not cutting it. The property had an EICR done a few months ago but no concern over higher readings on socket radial for the down stairs sockets including the kitchen being on a 16a 2.5 cable your comments would be appreciated

 

[l4urence]

I’m getting the feeling this might be a final ring broken into 2 radials - but maybe not correctly. Do you see 2 radials that could have been a ring. What you are describing doesn’t make sense. It’s factual and correct but nonsense at the same time. Your further investigation is crucial.

 

[John tomo 1972]

Thanks for your feedback guys. It very much appreciated. rfc it is. As it stands it not right in my eyes and needs sorting thanks again for the advice

 

[John tomo 1972]

Thanks for your feedback guys. It very much appreciated. rfc it is. As it stands it not right in my eyes and needs sorting thanks again for the advice

 

[John tomo 1972]

I did notice a cable cut out int the kitchen and thought that myself I have asked the buyer to contact the previous owner to see if they could shine any light on any work that’s been done prior the sale

 

[l4urence]

I’m getting the feeling this might be a final ring broken into 2 radials - but maybe not correctly. Do you see 2 radials that could have been a ring. What you are describing doesn’t make sense. It’s factual and correct but nonsense at the same time. Your further investigation is crucial.

I did notice a cable cut out int the kitchen and thought that myself I have asked the buyer to contact the previous owner to see if they could shine any light on any work that’s been done prior the sale

This is important. You might well have found the reason this is a such conundrum.

 

[DefyG]

I’m not comfortable with the fact downstairs sockets and the kitchen are all on a 16a what do you think.

Nor would I be. Kettle and a toaster alone are likely to cause an overload and trip!
The readings for a radial are possibly ok but if a significant jump in Zs between sockets (unless long run of cable) then further investigation required as previously suggested.
As it is an EICR recommend upgrading to

 

[Electric Magic]

Nor would I be. Kettle and a toaster alone are likely to cause an overload and trip!QUOTE]

A little pedantic of me but if it's a fairly typical kettle (3kw rating) and toaster (2kw rating) then they may not cause the MCB to trip at all as they will be pulling up to 21.73A max and (from memory so could be slightly off) MCBs must, as a minimum, trip at 1.45 times their rating in under an hour, in this instance 23.2A, so 21.73A may not be enough to make it trip ever, let alone within the 5 minutes the kettle is on.

 

[westward10]

I had to split a ring final in a non domestic premises last week, open cpcs which could not be rectified. Ended up with five outlets on one, seven on the other. Zs for one 0.64 the other 1.66. The low reading the first part of the circuit the high one went all the way over and back to the middle.

 

[DefyG]

Electric Magic said - A little pedantic of me.

Just a bit I could have used 'dishwasher' and 'washing machine' as an example but you get the picture!

 

[John tomo 1972]

Thanks again for your comments. Just to update. I called the previous owner and asked if they could shed any light and after 10 minutes of uming and aring told me that he had an issue with the downstairs ring so the electrician he used cut one leg of the RFC and layed another cable to it and the rest is still on with the kitchen 16a