How to check if a fuse feeds a ring final or 2 radial circuit

[Des 56]

I was thinking about this recently. I don't think that the cross-connection method is particularly reliable for checking the configuration of a ring circuit where you have, for example a very short spur with more than one socket, where the additional resistance produced is minimal.

Obviously measure ring continuity, IR, Zs, etc. as usual.

Thoughts?

A couple of thoughts of mine Handysparks

Good thinking and I seem to agree with the outcome that ring continuity would be assured,but it also seems to entail major disruption at every socket, having to disconnect then test remotely at the dist board for each item and do so 3 times per socket,it would seem to be one very time consuming exercise

The main weakness I see is that the test is also a test of polarity and although the tester is likely to reconnect the items correctly,bad things do sometimes occur and this test would mean it is then down to a plug in jobbie or reliance on not getting it wrong ever

 

[Midwest]

Well you obviou

Just trying to show the OP the complexity, of a RFC test and the need for the correct equipment, a multimeter is no good for this test, not something for what is a DIYer or in this case a Handy man, who in all honesty shouldn't be fluffing around with something he has very limited knowledge, these videos are very informative for trainees etc, absolutely not to be used by non sparkies

Pete never linked up your post with OP's response, so no offence meant.

 

[Pete999]

Well you obviou

Pete never linked up your post with OP's response, so no offence meant.

None taken Mate

 

[Midwest]

Coolio

 

[Darkwood]

Another point I didn't see raised is if he in fact managed to get test results there is the issue of knowing how to interpret them, understanding what they mean and when action needs to be taken, a high ohms reading end to end may be dealt with differently by a professional as oppose to a DIYer, just because it shows a closed loop doesn't mean its safe to energise.

 

[kingeri]

Another point I didn't see raised is if he in fact managed to get test results there is the issue of knowing how to interpret them, understanding what they mean and when action needs to be taken, a high ohms reading end to end may be dealt with differently by a professional as oppose to a DIYer, just because it shows a closed loop doesn't mean its safe to energise.

I touched on it near the beginning:

To verify if it is a ring, you need to access every socket outlet on the circuit in turn (you will likely have to unscrew them all), after making temporary connections in the CU. You also need to know how to interpret the results obtained from your 'multi meter'.

 

[Darkwood]

So you did @kinger, my apologies... I just skimmed the answers and missed your note on the matter

 

[The Ghost]

I think I might be more concerned as to why suddenly are there fuses going so regularly, what is going on with the sockets if they did not do this before. You might find a temporary answer if you knew what they are plugging in when the fuse goes and encourage them not to. What do you think? At least until it can be investigated more thoroughly. Might be faulty equipment or overload from too many things on at the same time.

 

[HandySparks]

A couple of thoughts of mine Handysparks

Good thinking and I seem to agree with the outcome that ring continuity would be assured,but it also seems to entail major disruption at every socket, having to disconnect then test remotely at the dist board for each item and do so 3 times per socket,it would seem to be one very time consuming exercise

The main weakness I see is that the test is also a test of polarity and although the tester is likely to reconnect the items correctly,bad things do sometimes occur and this test would mean it is then down to a plug in jobbie or reliance on not getting it wrong ever

True. Certainly more disruptive that the conventional 'figure of eight' test.
I was really trying to think of a guaranteed way of proving a ring, as I often find that contact resistance makes for uncertain readings.

 

[mydigitalhome]

Nice to see Kris Kitcher again well known for his books and lecturing at Uni. in YouTube video

 

[247 handyman]

I think I might be more concerned as to why suddenly are there fuses going so regularly, what is going on with the sockets if they did not do this before. You might find a temporary answer if you knew what they are plugging in when the fuse goes and encourage them not to. What do you think? At least until it can be investigated more thoroughly. Might be faulty equipment or overload from too many things on at the same time.

In my opinion they recently had a boiler fitted the old system was obviously removed. Some how they blew the 30a fuse so swapped the now redundant 15a fuse into the 30a carrier. When the high draw loads from the kitchen started to blow the 15a fuse as all the house sockets are on 1 fuse.

 

[The Ghost]

recently had a boiler fitted

I certainly would be calling them back to rectify that as they have, by what you say, underfused the existing circuit and should be obliged to rectify it.

 

[247 handyman]

I certainly would be calling them back to rectify that as they have, by what you say, underfused the existing circuit and should be obliged to rectify it.

Problem is we have no proof it just looks to be something along those lines. All the carriers had fused in but now there is a 30A fuse missing and a 15A in the red carrier and an empty 15A slot.

 

[Pete999]

Problem is we have no proof it just looks to be something along those lines. All the carriers had fused in but now there is a 30A fuse missing and a 15A in the red carrier and an empty 15A slot.

Hasn't the boiler got a fused spur feeding it with an appropriate size cartridge fuse fitted?

 

[Midwest]

In my opinion they recently had a boiler fitted the old system was obviously removed. Some how they blew the 30a fuse so swapped the now redundant 15a fuse into the 30a carrier. When the high draw loads from the kitchen started to blow the 15a fuse as all the house sockets are on 1 fuse.

OP, assuming your in-laws house is a typical small pensioners property, I'm wondering why the 15a fuse is blowing? Again assuming its going after a period of time? What have your in-laws plugged into their sockets,any electric fires. Most modern appliances draw moderate amounts of load. Or does the fuse blow suddenly, e.g. when the boiler system is turned on?

 

[247 handyman]

OP, assuming your in-laws house is a typical small pensioners property, I'm wondering why the 15a fuse is blowing? Again assuming its going after a period of time? What have your in-laws plugged into their sockets,any electric fires. Most modern appliances draw moderate amounts of load. Or does the fuse blow suddenly, e.g. when the boiler system is turned on?

No pal it's quite large. Was a typical council house which they bought and extended then had a loft conversion. Going from 3 bed to 6. Big family but only 2 "kids" left at home. Usually seems to be in the morning with washer dryer heater hair straighteners at all running.
Never had a problem with everyone at home, it only started with the cold weather the other week. There is only 1 circuit for all the sockets including the kitchen.
I'll say again I'm totally convinced someone has changed the fuse but I won't let them change it back without it being tested.

 

[247 handyman]

Hasn't the boiler got a fused spur feeding it with an appropriate size cartridge fuse fitted?

No pal. The boiler is just plugged into a normal socket.

 

[Pete999]

No pal. The boiler is just plugged into a normal socket.

Who installed the boiler?

 

[247 handyman]

Who installed the boiler?

Wife is checking with her mum.

 

[247 handyman]

Wife is checking with her mum.

Sorry she can't remember.