Continuity values keeps going down.

[shocksl]

So bought a second hand Megger BM233 to practice with as I'm a college student..

So I was just using it on a loose 2.5 cable. Testing on the neutral from both sides . Whilst having the device on the Ohm side. I nulled it to zero by touching the probes.

When I do the dead test. It starts off with figures likes 0.22 . Then goes downwards until it gets to 0.0 and sometimes even with a negative -0.0

Does anyone know what this is?

 

[DPG]

At those low values the resistance at the contact points of the test leads is significant. Are you clipping your test leads on to the cable?

Don't worry about the 0.00 or -0.00

 

[timhoward]

Whilst having the device on the Ohm side. I nulled it to zero by touching the probes.

I presume you pressed test too, as this does the nulling?
Then to ask the obvious, I presume you are NOT pressing test when you put the clips on your test cable?
(Anyone used to other testers makes this mistake at first with Meggers)

 

[shocksl]

At those low values the resistance at the contact points of the test leads is significant. Are you clipping your test leads on to the cable?

Don't worry about the 0.00 or -0.00

Yes I'm using Croc clips.

 

[shocksl]

I presume you pressed test too, as this does the nulling?
Then to ask the obvious, I presume you are NOT pressing test when you put the clips on your test cable?
(Anyone used to other testers makes this mistake at first with Meggers)

Yes I press the test to null and then I don't press the test again when I'm testing as it does it automatically.

 

[littlespark]

The fact that its a "second hand" tester may be a clue.

Does it give proper readings testing other things?

 

[DPG]

Good advice from littlespark. Can you get hold of some known resistance values?

I can send you some assorted resistors for free if you want so that you can test it throughout its ranges.

 

[shocksl]

The fact that its a "second hand" tester may be a clue.

Does it give proper readings testing other things?

No I haven't tried it anywhere else . Other than the oose cable.

 

[shocksl]

Good advice from littlespark. Can you get hold of some known resistance values?

I can send you some assorted resistors for free if you want so that you can test it throughout its ranges.

Oh that's really kind of you!.

 

[DPG]

Oh that's really kind of you!.

Pm me. I'm going away tomorrow afternoon for a week though. Might be able to get some in the post tomorrow.

 

[shocksl]

Pm me. I'm going away tomorrow afternoon for a week though. Might be able to get some in the post tomorrow.

Thanks mate PMd you.

 

[DPG]

Thanks mate PMd you.

I'll get some in the post tomorrow all being well. Your meter only goes up to a shade under 100 Ohms on its continuity range, so no need for any high values.