Testing ring main with a spur

[445]

Hi currently at college doing level 3 testing and inspection just a few questions if anyone can help

For the Ring circuit it is all wired in 2.5 singles and has one spur off the the ring
After doing end to end tests is the calculation r1/2 seen as though the cables are the same size?
Also if there is a spur and is the highest reading do i write this down for the R1+R2 of the ring circuit Thanks

 

[Sparky Ninja]

VerIfy the R1&R2 readings from the spur, but record the highest reading obtained on the ring. If the spurs reading is very high due to length of cable etc then it may be worth recording also.

 

[chris gray]

personally id record the higher of the two readings, more than likely at the spur.

 

[mogga]

Imo the spur is part of the circuit hence if thats the highest reading that goes in the box Miss read Op Im meaning Zs

 

[445]

So when i am checking the R1+R2 do i add r1+r2/4 or r1/2 as all the conductors are wired in 2.5mm2 singles Thanks again

 

[WayneL]

So when i am checking the R1+R2 do i add r1+r2/4 or r1/2 as all the conductors are wired in 2.5mm2 singles Thanks again

Hi mate,

You can do it either way - you'll get the same answer.

Don't forget, this calculation is just to give you an idea of the reading to expect when you actually measure R1 + R2.