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  1. J

    Zs and parallel paths...

    Hi all, easy question I’m sure, so hope someone can clear up for me. If there are parallel paths on a circuit upon which Zs is being measured, will the parallel path cause the Zs to go up or down, and could someone explain why this would be so at all? I just need a clear understanding of this...
  2. C

    Career paths

    Bit of info about me first of all im 18 on an electrical installation apprenticeship doing my level 3 this September got all distinctions in level 2 B in maths A in all sciences Just wondering once i have qualified what other qualifications should i go after and what is the highest paid...
  3. D

    Parallel paths on R1 + R2 test

    Hi there Doing some testing at moment. R1 + R2 readings coming in lower than R1 + Rn. Cpc neutral and live all disconnected. There is alot of containment on job and adaptable boxes are all fly leaded to earth. My thoughts are they are parallel earth paths but guy working with seems to think...
  4. G

    An old newbie forced to change paths

    hi guys I hope I can give you a bit of back ground then you'll all see my situation, I ve spent a long while as a motorcycle mechanic ( when I was much younger) I spent ten years as a have 1 driver and I have just spent the last nine years working in social housing, unfortunately I have been...
  5. 1


    Hi guys R1+R2 on a eicr mates tutor on the 2395 course said no need to carry out just zs is enough and on ring just end to end readings what's everyone's thoughts on this
  6. S

    Seems quiet tonight, so...

    Given a chessboard (8 x 8 square grid) and a piece which is only allowed to move one square upwards or rightwards (it cannot move diagonally, downwards or left). The piece starts in the bottom left corner of the board and you have to move it to the top right corner. There are clearly lots of...
  7. D

    problems with Zs testing

    Hi! I was measuring Zs on a lighting circuit some time ago. First I did R1+R2 and it was around 1.60, pretty high but there were a few connections on the way and most of the cable was 1.0mm. Ze measured at the CU was low about 0.10 only, so Zs altogether around 1.70. When I measured it using...
  8. A

    Ring Final Circuit Problem

    Hi all hope you can help had a spur to fit on an old ring final circuit today that is made up of the old 3092 and old twin and earth were it has been extended in the past the readings i got end to end L 0.16 N 0.16 E 0.32 added together 0.16+0.32/4 = 0.12 but when i carried out a figure of 8 i...
  9. H

    Series and Parallel

    Hi everyone, first of all great site with some real great answers on here. I have a question which might sound silly but can't get my head around it. Series and parallel. Can anyone give me a practical real world example of the two? I've got my 2391 next month and I really don't understand what...
  10. J

    method of finding R1+ R2 of circuit

    Why is Zs-Ze not a approved method of determing the R1/R2 of a circuit
  11. B

    RCD question

    Hi people can anyone tell me the difference between the tripping currents and the current ratings of rcds.Any help I would be thankful of
  12. A

    Prospective Fault Current

    Hi Guys How do you calculate Prospective Fault Current?? Wouldi be correct in thinking it is nominal voltage divided by Zs + R1 + R2 ??? So Nominal Voltage Zs + R1 + R2 A
  13. zone77

    testing Zs and Ze

    when i measure Ze from a DB ( disconnecting main bonding) am i suppose to reconnect bonding b4 testing Zs on final circuits. on job 2day some Zs from sockets was lower than Ze:confused:. i put this down to parralell paths but am i doing it correctly??
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