0.00 on earth ring test?

[Delboy247]

Trying to get my head around this doing r1 rn r2 test on a ring circuit today in metal conduit ran in singles, the r1 and rn where fine but when I came to the the r2 tester kept on recording 0.00 why little confused or is it obvious thanks in advance.

 

[Sparky Ninja]

Are the cpc's connected to the conduits possibly?

 

[Delboy247]

That's what i was thinking so how do I go about doing the r1 + r2 test ?

 

[IQ Electrical]

I agree with Widdler, are cpc's just going to earth couplings on top of the socket boxes?

 

[Delboy247]

There are two earths at each point.

 

[Sparky Ninja]

You can attempt the R1&R2 connection at the CU and go round. If you find the values very low, it is likely that conduit is being used as the cpc or is at least bonded to the cpc. In this case, you can carry on with the R1&Rn respectively, and then take an R2 measurement from the CU to each point.

 

[i=p/u]

wonder lead????? or is that radial circuits just????

 

[IQ Electrical]

Yes, you'd need a wander lead

 

[Farmelectrics]

its because the conduit and metal clad sockets are all earthed ie you are picking parrallel paths up you have to disconnect earth strap from back boxes conduit etc

 

[Delboy247]

Ok so I fill in R2 (at least one colum to be completed)using a wonder lead but what do I write in the r2 (cpc) colum n/a?

 

[Farmelectrics]

the wander lead would give you the same reading you need to disconect eart cable from steel work ie conduit

 

[IQ Electrical]

No, the wander lead is used between the earth bar and each outlet, the results will be different but low with conduit and cpc's but this is fine, you only need to enter a value in the R1+R2 box OR the R2 box.

 

[Farmelectrics]

dissconect earths to back boxes and conduit i no its stripping job down but its only way to get true reading of r1 r2

 

[Farmelectrics]

this is not a true reading your picking up parrallel paths

 

[IQ Electrical]

If this is a PIR, please don't start stripping anything down, just record R2 as it is measured.