Continuity

[Nijinski001]

Guys
Test equipment calibarted and working and books in hand I have just done my first PIR practice on my sisters home and come across what I regard as some strange numbers.
What is your take on the results?

Continuity R1+R2 readings on the light circuits upstairs read from 0.02 to 1.24 across 5 different ceiling roses. This seems low.

I also have R1+R2 readings on ring sockets that appear to be the same as the continuity reading on the ring its-self. Shouldn't the sockets be substantially lower than the ring?

Am I doing something wrong?
I have followed the test procedures written down to the letter.

Cheers

 

[andy]

Continuity R1+R2 readings on the light circuits upstairs read from 0.02 to 1.24 across 5 different ceiling roses. This seems low.

there is a longer length of cable as lights are radial, so you would expect it to get higher as you work your way along the radial. its the highest number that you write down

I also have R1+R2 readings on ring sockets that appear to be the same as the continuity reading on the ring its-self. Shouldn't the sockets be substantially lower than the ring?

R1+R2 on a ring should be the same throughout since its a ring. altho it would go up slightly for spurs. not sure what you mean by

'Shouldn't the sockets be substantially lower than the ring?'

 

[Qedelec]

1.24 sounds ok for a small property lighting circuit, 0.043 per metre 1.0m phase and cpc.
++++++++++++++++++++++++++++++++++++++++++

By the way nij did you know that you can save a fortune on recalibration by instigating a regime of monthly testing against a test box.

By logging results on a regular basis you are ensuring the calibration is not drifting.
If you want a copy of a test form, mail me and I will send you a copy by return.
__________________
"Shock me again and I'm gonna turn you off"
Life's a beach.

MOD

please use the edit key

 

[ban-all-sheds]

I also have R1+R2 readings on ring sockets that appear to be the same as the continuity reading on the ring its-self. Shouldn't the sockets be substantially lower than the ring?

If you've cross-connected phase and cpc at the CU, then the readings at each socket should be substantially the same - they will vary slightly because phase & cpc are different sizes.

 

[Nijinski001]

Thanks for all the replies guys.
Andy, I understand the concept of the radial thanks but I was questioning how low the readings were. Or is 0.02 to 1.24 within the normal band expected?

 

[Qedelec]

1.24 ohms is about 30 metres, does it look that long?

 

[Nijinski001]

I suppose it could be if the circuit doubles back. The sequence of readings indicate it could possibly.

Thanks

 

[pdcelec]

Andy, I understand the concept of the radial thanks but I was questioning how low the readings were. Or is 0.02 to 1.24 within the normal band expected?

Are you saying that you do not understand the basics?


From a previous post:

Guys
I'm now officially competent and have all the test equipment Alphatek can throw at me. I'm branching into PIR for rented properties.

How did you manage this? From the questions above, I would like to know who passed you off as competent. Is becoming Part P registered really that easy?.

 

[andy]

Is becoming Part P registered really that easy?.

providing you have the money, then yes