Testing Your Pat Testers Earth Bond Test Lead

[stev228]

Hi

I just  bought a second hand    metrotest mpat10

and it seems to work ok and i will be getting it recalibrated soon

my question is I tested the earth bond lead by connecting it to a plug  earth pin inserted  in the 240v test socket earth

so the tester was just testing its own earth bond  lead ...(.I know probably not good practice )

and it came back with a reading of .03 ohms which i confirmed with my fluke low reading ohm meter

Now what i want to know is is this normal as the ohm reading seems to be  correct for the earth test lead itself and  if so do you then take .03 ohms off your lead  calculations to allow for the meters own resistance of its own  test lead

As any mains lead tested will actually be .03 higher than it actually is

has anyone else noticed this

it could be that my tester needs calibrating with an offset to cater for its own  test lead resistance

or it just might be the way it works anyway so it will fail higher reading leads

i dont have any other information maybe someone out there knows the answer

I did try speaking to seaward as they do a similar meter\clone  but they did not read my question properly and went on about  lead length software that they could sell me

So i thought i would try here and maybe get a sensible  answer

thanks for your time reading this and maybe you have an answer

 

[Andy™]

probably be an option of the meter to zero the lead

 

[ProDave]

I would only worry about it if your test result is within 0.03  hms of a pass / fail