P.F.C using a megger 1553 advice plz

[voltage]

Hi all

A question reguarding P.E.F.C and P.S.C.C using a megger 1553

Now i know this is a live test so lets say ive safely isolated ive got my megger im using the 2 wire lead option green and red.

So the board has RCD protection so i set my megger to the NO TRIP PFC ? CORRECT ?

Then test between LINE + EARTH for the P.E.F.C
Then test between LINE + NEUTRAL for the P.S.C.C

Then record the highest of the two results which = the PFC worst case scenario ? correct this is on a TNCS system by the way.

help would be appreciated many thanks volt

 

[IQ Electrical]

Hi all

A question reguarding P.E.F.C and P.S.C.C using a megger 1553

Now i know this is a live test so lets say ive safely isolated ive got my megger im using the 2 wire lead option green and red.

So the board has RCD protection so i set my megger to the NO TRIP PFC ? CORRECT ?

Then test between LINE + EARTH for the P.E.F.C
Then test between LINE + NEUTRAL for the P.S.C.C

Then record the highest of the two results which = the PFC worst case scenario ? correct this is on a TNCS system by the way.

help would be appreciated many thanks volt

Sounds spot on but if you can test on the supply side of the RCD without using 'no trip' (assuming it's within the DB) then your PFC reading will be more accurate.

The black lead on the 1553 will stay connected to the neutral bar throughout the 2 tests.

Your PEFC and PSSC should be almost identical on a TN-C-S system.

 

[malcolmsanford]

If it is on a TNC-S chances are the results would be the same.

As for the Meggar, I'm not a meggar man but I would have thought it would be the NO TRIP setting to be honest.

 

[voltage]

thanks guys for the fast responces much appreciated.

 

[voltage]

Sounds spot on but if you can test on the supply side of the RCD without using 'no trip' (assuming it's within the DB) then your PFC reading will be more accurate.

The black lead on the 1553 will stay connected to the neutral bar throughout the 2 tests.

Your PEFC and PSSC should be almost identical on a TN-C-S system.

Im a bit confussed now ahh forgive me i just noticed on the megger the top hole has the NO TRIP LOOP so this would be the neutral which would be connected thoughout the test ? correct ?

So the test would be a 3 lead test in reality then ? not a 2 as i thought ? is this correct ? many thanks volt

 

[IQ Electrical]

Im a bit confussed now ahh forgive me i just noticed on the megger the top hole has the NO TRIP LOOP so this would be the neutral which would be connected thoughout the test ? correct ?

So the test would be a 3 lead test in reality then ? not a 2 as i thought ? is this correct ? many thanks volt

I wasn't too clear there, if you can perform the test without using 'no trip' then it's a 2-lead test.

Using 'no trip' it's a 3-lead test.

 

[malcolmsanford]

I wasn't too clear there, if you can perform the test without using 'no trip' then it's a 2-lead test.

Using 'no trip' it's a 3-lead test.

Not being a meggar man in the 2 test lead for no trip. Do you have to link the blue/green leads together of just use the red/green leads.

 

[richy3333]

I tend to use the Hi setting on the megger (- 4th along on the green area of the dial, if you know what I mean.) 2 lead test for PFC to earth and neutral

 

[Sintra]

Don't need to link leads on the megger just have red & green plugged in.


Sent from my iPhone using Tapatalk.

 

[voltage]

I tend to use the Hi setting on the megger (- 4th along on the green area of the dial, if you know what I mean.) 2 lead test for PFC to earth and neutral

yeah i can what you mean on the megger says HI PFC LOOP so this way i could just use RED and GREEN leads ?

So the test would be LIVE TO EARTH ?
LIVE TO NEUTRAL ?

 

[IQ Electrical]

yeah i can what you mean on the megger says HI PFC LOOP so this way i could just use RED and GREEN leads ?

So the test would be LIVE TO EARTH ?
LIVE TO NEUTRAL ?

Yes, no need for the 3rd lead on the full test.

 

[telectrix]

yeah i can what you mean on the megger says HI PFC LOOP so this way i could just use RED and GREEN leads ?

So the test would be LIVE TO EARTH ?
LIVE TO NEUTRAL ?

that's how it is on the 1552. don't use no trip.

 

[voltage]

Reading through the megger leaflet quick start guide reguarding this PFC TEST

non tripping loop test [NO TRIP]

Select when testing ciruits with RCD protection fitted it says

High current loop test [HI]

for use on circuits with no RCD protection fitted

No trip PFC measurement [NO TRIP PFC]
phase to earth PFC

 

[telectrix]

yes, but you only use no trip when measuring after the RCD, not before it

 

[voltage]

yes, but you only use no trip when measuring after the RCD, not before it

Thanks i get it now

So the test i would use on my TNCS system and the consumer unit being a MK dual RCD board would be

To set the megger onto the HI loop setting into the green area
then test form LIVE TO EARTH then LIVE TO NEUTRAL and record the highest reading as my PFC ?