Exam next week Zs

Trevor R · Jun 23, 2011

Hi

I have the 2392 next week and will need to do all of the dead \ live tests - I am
happy in principle but getting confused with the meter setting (using megger 1553)

I think the problem is terminology - when I want to check Zs is this what the manual
describes as Non Tripping Loop test [no trip]?

If it is am I correct in that this is a 3 wire test and will return a value of ##ohms

Thanks

i=p/u · Jun 23, 2011

think is two wire test with mft 1553 and yes youl get reading in ohms, read the manual that comes with tester, they all different or are the same if you get me

Trevor R · Jun 23, 2011

Have read the manual - the manual does not mention Zs is Zs a non tripping loop test [no trip] - if they are one and the same then the manual states that the 2 wire is for a non RCD protected circuit.

The circuit I am testing has RCD so using 3 wire - the manual says that the L-PE loop value is displayed - is this the Zs

Thanks

i=p/u · Jun 23, 2011

i think so and then you check you on site guide and see does it comply or you can calculate like this say you testing 6A mcb tybe b

6 x 5 = 30 dived by 230v = 7.6 ohms which youl see in book is correct

tony mc · Jun 23, 2011

When using the Megger 1553 and you are on the No Trip you need a neutral connection or it will not connect the meter will beep when power is applied.

tony mc · Jun 23, 2011

Just read your post again.

When doing a live ZS on a cct you need to be in the green zone of your MFT marked LOOP.

If the cct has a RCD or a RCBO then you need to be on the NO TRIP setting in the green zone and a neutral connection needs to be made.

The reading will be in Ohms which will be displayed on the screen.

Hope this helps

tony mc · Jun 23, 2011

This might help get your head around a few things.

2391 sum practical help

2392 2391 2398 2734 2980 24561 2371 or even 2999 the testing is the same have a look.