METREL "EASITEST" Zs PROBLEMS

[greeny]

Hi all, I am pleased to be onboard with you all and looking forward to joining in with the forum activities.

My reason for my new interest in this site today is this.

I have a "Metrel Easitest" multifunction test set and ever since I had it I have never trusted the trip lock readings of Zs. For instance on an expected Zs of say 0.4 ohm I get readings variant from 0.01 to 1.9 ohm.
I have done a trial test with 20 readings, it took a long time and I then obtained an average which is very close to expected results but why should this be. Is this normal for this test set/other test sets, or a fault.

With the 17th edition trip lock is even more necessary, so should I ignore the trip lock facility and just add ,measured Ze to R1+R2, previously measured on continuity, and record the Zs result that way.
Help please

 

[devlin maguire]

Hi Ihave the Metrel euro test Mi3002 and on the Zsrcd setting I also get readings that do not concur with Ze + R1+R2 valies calculated from tests, it also goes in and out of calibration after nulling out leads etc maybe a Metrel thing. I intend to get onto tech Monday morn as this tester is only months old
in the meantime maybe best sticking with the formulae above that you know and love so well
Mac

 

[greeny]

Hi Mac, thanks for your help please let me konw how you get on when you speak tothe Metrel Tec guys.
Greeny

 

[Markc]

Hi

We run all Metrel test gear and have had problems but once we voiced our disgust rather loudly with the Metrel rep one day we got two of our meters changed FOC.
Few questions. 1. Are you on Zsrcd setting? 2. Are you using three leads? 3. Are you using the tip commander? 4. Is your R1 + R2 correct due to nulling leads?

If you are on Zsrcd then it will test using a 25amp balanced test so hence the RCD will not trip (And to give Metrel their due I have yet to find a RCD it will trip)
You can only use a three lead or plugtop lead to test Zs though a RCD. Balance issue again. If you are using the tip commander then throw it away. The components in it throws the readings.

The other thing to consider is are the R1 + R2 readings correct. We had issues and ended up making up a link out socket with a 1gang trailing lead socket and the socket and see plugtop link unit. The one with the three round holes to accept the leads directly. Now we know are leads are nulling correctly rather than just holding them together we get much better readings.