R1+R2 of zero zilch nothing?......

[Baddegg]

Testing R1/R2 on 10mm/4mm T&E cable and the reading is 0.00? Never had this before, can I record 0 on the cert?

 

[littlespark]

Check your leads and batteries in your tester. No way can it be zero.

Unless you nulled the leads while connected to the cable?

 

[Baddegg]

Checked leads,nulled before testing,took one croc off and tested open circuit put leads on and put testers in hands free then operated the isolator switch in the circuit and it switches between 0 and open circuit...it’s about 8 mtrs max cable run,

 

[westward10]

You cannot record zero on the cert as this would be incorrect, the cable is 8m long there must be some measurement of resistance there.

 

[Baddegg]

Yes that was my concern I can’t record 0,the testers are calibrated and the batteries are fine it’s brand new 10mm cable...is there any percentage or tolerance +/- on R1-R2?

 

[Octopus]

I would try your tester on a longer piece of cable - with a smaller CSA

The reading for the 10mm would be around 0.06 ohms ........

How old are your tester leads ?

 

[Pete999]

Testing R1/R2 on 10mm/4mm T&E cable and the reading is 0.00? Never had this before, can I record 0 on the cert?

Are you doing the testing correctly?

 

[Baddegg]

Yes that’s my plan for tomorrow Murdoch,leads are less than a year old

 

[Baddegg]

Are you doing the testing correctly?

Thinks so,R1-R2 joined at board, disconnected at appliance, leads nulled, switch closed,croc on R1 croc on R2 test? Got Ze of 0.18 on tncs previous...

 

[Grant webber]

Could be to low for your tester. Test it with out the leads nulled then deduct the test lead resistance off afterwards

 

[Baddegg]

Could be to low for your tester. Test it with out the leads nulled then deduct the test lead resistance off afterwards

Never thought of doing that,thanks grant,using kewtech kt63 if that helps never had any issues before with it...

 

[Pete999]

Thinks so,R1-R2 joined at board, disconnected at appliance, leads nulled, switch closed,croc on R1 croc on R2 test? Got Ze of 0.18 on tncs previous...

What scale have you set on your MFT?

 

[MDJ]

What scale have you set on your MFT?

Exactly what I was going to ask

 

[Baddegg]

Sorry Pete and mdj,on my testers you just select continuity if there is a scale selection I’m not aware of it?...

 

[Silly Sausage]

Never thought of doing that,thanks grant,using kewtech kt63 if that helps never had any issues before with it...

I'd put it down to calibration error combined with your meter's accuracy. Looking at the spec, you've +/- 2 digits on continuity, meaning if it was perfectly calibrated and you were measuring a known resistance of, say, 0.05Ohm, the reading could be anything from 0.03 - 0.07 Ohm. It's what happens when trying to take measurements at the bottom end of the scale.

Record it as 0.01, or if you know how long the cable actually is, work it out from the tables.