megger 1553 multi functional tester

[semaphore]

Hi guys,

We were testing an install the other day with a new meter megger 1553.
Ze is a LIM as we cannot disconnect earthing
Could not test IR on this circuit due to electronics connected.
Did long lead R2 but it's all conduit with no separate CPC and no fly leads at accessories but has plastic fittings. Then tried Zs but it comes up on display as "Trip" and does not give a reading but does not actually trip the 10A 3871 type 3 breaker
Went and got old Fluke 1652 from van but it's out of calibration and tried it with that using the 3 leads but still no joy.
I assume it will not give a reading as a safety measure as the touch voltage may rise too high due to poor insulation resistance? But this is just a guess. I can't find any documentation on this.
I have now emailed Megger but they have not got back to me. I just thought someone on here might know. Cheers

 

[Guest123]

Hi guys,

We were testing an install the other day with a new meter megger 1553.
Ze is a LIM as we cannot disconnect earthing
Ze cannot be a "LIM" you obtain by enquiry.
Could not test IR on this circuit due to electronics connected.
Could you not have measured L&N together to E???
Did long lead R2 but it's all conduit with no separate CPC and no fly leads at accessories but has plastic fittings. Then tried Zs but it comes up on display as "Trip" and does not give a reading but does not actually trip the 10A 3871 type 3 breaker This is because as you've said the meter cut out on the test as the touch voltage rises above the safe threshold.
Went and got old Fluke 1652 from van but it's out of calibration and tried it with that using the 3 leads but still no joy.
I assume it will not give a reading as a safety measure as the touch voltage may rise too high due to poor insulation resistance? But this is just a guess. I can't find any documentation on this.
I have now emailed Megger but they have not got back to me. I just thought someone on here might know. Cheers

I'm confused, you say you did an install, was this a new install or just additions and alterations to existing???

I'll reserve judgement until you clarify your situation a bit.

 

[semaphore]

Lenny

Sorry I should have said it was a PIR.
And I've found out now what the problem is.
There are 3 single phase isolators in the switchroom/plantroom (well loads more really but these are the ones affecting it) and you need to disconnect all 3 to Isolate any one phase.
So there's a voltage of about 120v on this circuit when isolated, therefore the meter won't allow a test. It's just the "Trip" message I was unfamiliar with on this meter and could not find reference to it in the manual (still can't).

Also can't do IR - L+N to earth without disconnecting the earth(s) (not possible) and an ELV safety circuit has also been connected to this circuit - not good!

Thanks anyway

 

[Guest123]

Good show.

 

[johnstantine]

The 1553 will also come up with TRIP if you accidentally break the connection with your probes during testing.

 

[trebor]

Hi guys,

We were testing an install the other day with a new meter megger 1553.
Ze is a LIM as we cannot disconnect earthing
Could not test IR on this circuit due to electronics connected.
Did long lead R2 but it's all conduit with no separate CPC and no fly leads at accessories but has plastic fittings. Then tried Zs but it comes up on display as "Trip" and does not give a reading but does not actually trip the 10A 3871 type 3 breaker
Went and got old Fluke 1652 from van but it's out of calibration and tried it with that using the 3 leads but still no joy.
I assume it will not give a reading as a safety measure as the touch voltage may rise too high due to poor insulation resistance? But this is just a guess. I can't find any documentation on this.
I have now emailed Megger but they have not got back to me. I just thought someone on here might know. Cheers

When you did your Zs were you using the mains lead or fly leads ?

The usual error that causes the trp display is
.Measuruing Zs on low current setting without the third lead ( black goes in no trip at top) test at fitting black on neutral green on earth etc, these must be secure connections , any movement during the test will cause the to display trp