Continuity Of Water Service Earth...

[SSE]

Brand new 10mm cable been installed yet I'm getting a reading of 1.26 ohms?? Rather high is it not?

 

[antimatter]

Very, have you nulled your leads first?

Sounds like you have the resistance of your test leads plus the resistance of the 10mm cable in your reading .

 

[AlanWirral]

Parallel paths?

 

[AlanWirral]

Arrrr yes null the leads ;-)

 

[antimatter]

Shouldn't be parallel paths, as you test ened to end on services like gas and water.

 

[AlanWirral]

I was looking at worst case scenario I'd have hoped he'd disconnected the end but you never know..

 

[malcolmsanford]

could be a really really long run .......................................if your using a wander lead then you will need to deduct the resistance of the lead, which is normally on the lead drum.

 

[telectrix]

parrallel paths would reduce the reading anyway. try a bigger screwdriver on the conns.

 

[armbands0]

Could be a poor connection between the pipe and the clamp, did you clean off any paint or oxidisation from the pipe?

 

[antimatter]

Could be a poor connection between the pipe and the clamp, did you clean off any paint or oxidisation from the pipe?

As previously pointed out, the conductor must be disconnected from the clamp otherwise p/paths will be introduced.

 

[antimatter]

Both, unless you can visually confirm continuity throughout its entirity.

 

[Deleted member 19807]

I would suspect a joint if testing is being done correctly

 

[SSE]

Hey, got it sorted. The batts were goin' flat in the Megger and I hadn't disconnected it from the earth clamp! Cheers anyway.

 

[Farmelectrics]

parallel paths would give you a lower reading and also a false reading

 

[Amp David]

If the cable is left connected to the clamp on your water supply and disconnected from the earth bar in the CU, how would a parellell path come into it anyway?

If a bonding cable is checked end to end with both ends being bare copper, then when its connected to the bonding clamp and the bonding clamp has a poor connection, then the resistance could be stupidly high, couldn't it?

 

[EastAnglian]

Which is why I will always do a second test once the cable has been terminated as I like to be certain the pipes themselves are connected as intended to the MEB