testing r1+r2 at cooker switches and cooker outlets

[r.b]

We all know that you take the highest of your readings etc when testing lights,sockets etc but how do you go on when doin a cooker circuit in exam conditions 2392?.Would you test at the main cooker switch with a cooker socket included for a reading plus at the cooker outlet with the main cooker switch on?.The highest of the two readings would normally be at the cooker outlet either or but whichever is the highest where should I be taking my earth loop reading later on in the tests?.Normally it would be where I got my highest reading is this write?.At the main switch I could plug it in with i.e.c lead take and take reading.At the cooker outlet I would have to take the cooker outlet off and take the reading.I just want to make sure where to do the tests from in exam conditions any ideas ?tb Ryan

 

[PC Electrics]

Ok, head above parapet time:

Now, don't get me wrong, I'm happy to help anyone. But....

Are you saying that you are studying for / about to take the 2392 exam?

If you are, can I suggest you study the testing section of the OSG (and preferably GN3 also). All this is explained in clear English in the OSG.

In particular pay attention to your definitions of r1, R1, r2, R2, rn and Rn.

Notice that r1 and r2 are values you can only measure on a ring final.

Failing to understand the meanings of terms used is a major cause of failure for this exam (and 2391 - see the chief examiners report).

retreats back behind parapet

---------- Post Auto-Merged at 14:12 ---------- Previous post was made at 14:03 ----------

You test your R1+R2 (or Zs if safe to do so) at the end(s) of the circuit, which is where you would expect to get the highest readings.

---------- Post Auto-Merged at 14:20 ---------- Previous post was made at 14:12 ----------

I personally would consider that it is safe to take Zs readings at a cooker outlet plate, since you only have to remove a simple cover and you can get in easily with your (insulated) probes. You should isolate the circuit to remove & replace the cover.

I would also consider it safe to take Zs readings at a batten or pendant, but I believe the NIC disagree with me on that one!

It is also perfectly valid to calculate Zs from Ze + (R1+R2).

 

[steptoe]

Ok, head above parapet time:Now, don't get me wrong, I'm happy to help anyone. But....

Are you saying that you are studying for / about to take the 2392 exam?

If you are, can I suggest you study the testing section of the OSG (and preferably GN3 also). All this is explained in clear English in the OSG.

In particular pay attention to your definitions of r1, R1, r2, R2, rn and Rn.

Notice that r1 and r2 are values you can only measure on a ring final.

Failing to understand the meanings of terms used is a major cause of failure for this exam (and 2391 - see the chief examiners report).

retreats back behind parapet

---------- Post Auto-Merged at 14:12 ---------- Previous post was made at 14:03 ----------

You test your R1+R2 (or Zs if safe to do so) at the end(s) of the circuit, which is where you would expect to get the highest readings.

---------- Post Auto-Merged at 14:20 ---------- Previous post was made at 14:12 ----------

I personally would consider that it is safe to take Zs readings at a cooker outlet plate, since you only have to remove a simple cover and you can get in easily with your (insulated) probes. You should isolate the circuit to remove & replace the cover.

I would also consider it safe to take Zs readings at a batten or pendant, but I believe the NIC disagree with me on that one!

It is also perfectly valid to calculate Zs from Ze + (R1+R2).

^^^+1