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  1. Steve888

    255V measured instead of 240V

    Hello while 255V seems to be a normal voltage for low voltage networks it causes issues to my solar installation where the inverter works up to 240V. Any idea why Western Power increased the voltage?
  2. S

    Measured kA on electraform EICS

    All, evening to you. I’ve started using electraform for doing certs. Doing an EICS and in the test results part there is a column next to measured Zs marked measured kA. I might be being special, but I’m not sure what I’d put in here for each circuit. Looking at my spare manually completed...
  3. Golden Graeme

    Minor works cert

    On the report is the earth fault loop impedance internal Zs or external Ze ?
  4. R

    High Zs on ring final circuit

    Good morning, I was recently at a job and had a discussion with another Electrician regards a high Zs reading on a ring final circuit. R1+R2 measured 1.68ohm Ze 0.18 Tncs This puts the circuit over the permitted zs. I begun seeking out the issue. However the other electrican said...
  5. V

    NICEIC Certification Scheme Niceic cert

    Hi all i have been filling in NICEIC certs now for the past two months the way our firm work is to give out what they call a site sheet we test and fill in the results and all the information and then the QS looks over it and finalises it, I was given a completed cert fully printed out from our...
  6. G


    Q, The earth fault loop impendence measured for a circuit is L1.1 0.61 determine showing all calculations weather it complies with Bs7671 what do I need to do
  7. P

    Earth Fault Loop Impedance

    Hi all, I am hoping someone can clarify if my understanding on earth fault loop impedance testing is correct. A low efli is needed so a protective decive can operate in the required time, the lower the z the quicker it will operate. ZE= External resistance from borad to supply, board...
  8. K

    Earth Fault Loop Impedence question

    hello, i got this qustion and would like someone to show me the working out of it please. the measured value of loop impedance for a circuit is 0.83 ohms. if the temperature at the time of the test was 20c and the cable is 70c (factor1.2), what is the correct value. ze = 0.4 ohms
  9. 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...
  10. P


    Hi all need some advice when filling out test results on eicr's after carrying out live zs tests do you leave out R1 R2 column as in a lot of cases the measured reading is below ze value do you just make a note that it is a measurement and not a calculation? any help appreciated
  11. M

    60V on light (pendant) with light switch off.

    Have been called to a recently installed installation. Customer noticed one of the GLS BC LED lamps was glowing when turned off. Here are the facts: Circuit tested - all tests appear normal. Wired with feeds at the switch. All lamps are LED Measured voltage when lights switched on is...
  12. S

    KEWTECH KT64 loop testing..

    hi guys when measuring loop empedans with kt 64 it gives me 2 option by chosing with f1 L-n l-pe which one shoul be used?? Thank you very much..
  13. Les Macaulay

    No live testing except where it's a must

    Do you agree that we only should be working dead when establishing the Zs for final circuits other than socket outlet circuits? That is, don't use the line, neutral and earth probes of the E/L tester except for Ze and Ipsc. Simply add R1+R2 to Ze.
  14. S

    testing measured or calculated

    Hi guys, I have my part p assesment in about 4 weeks. I have a kewtech kt61, it does everything i need it to apart from pscc. Will i be required to perform a manual pscc test or will calculating it be acceptable? As my tester doesnt do it. Thanks
  15. R

    Lighting Circuit Zs

    I must be confused about some wording, Light circuit R1+R2 is 1.84 Ze measured = 0.28 So if I do Ze +(R1+R2) I get 2.06 Maximum Zs allowed is 6.14 actual measured Zs is 0.88 This measured Zs is much lower than the max value, I know higher is not good but lower Zs leads to any problems ??
  16. V

    inspection & test, disconection times & maximum zs allowed

    Hi, on a tn system, 238vs, would the disconnection time be 0.4s or 0.2s, i thought as over 230vs it should be 0.2s, but working with another engineer who disdagreed & pointed out tables in bs7671 show 0.4s to 5s? Also when completing certs should you include the 80% or not in the maximum...
  17. L

    Prospective Fault Current

    Hi Guys, We measured PSCC on a three phase dist board in a commercial establishment. This board is fed from a main switch board with a main 400Amp switchfuse with BS88-2 fuses rated at 88kA. Feeding a second 160Amp switchfuse with BS88-2 fuses protecting the cabling to the board we were...
  18. mhar

    ce certificate for led's

    Looking around for gu10 led replacements. Obviously I know that ebay can hardly be described as a recognised distributor but they do have many sellers of and a wide variety of led lights. Apart from the normal worries about buying from such an 'outlet', I am concerned that the lumens figures...
  19. F


    two lighting circuit, one upstairs one down stairs, both on serparate rcds when i test down stairs at the last light for zs not a problem, when i upstairs at the last light, just beeps but doesnt give me a zs, why is that?
  20. O

    Resistance between Line and Neutral on a final ring circuit

    Hi After a bit of advice: I am just doing a bit of home testing prior to starting my 2391 later this month, but have come across a couple of strange results. Measured the R1 and got 0.98, also got the same for the Rn so not a bad start, but got 1.95 for the R2. I tested it a few times as I...
  21. A

    Industrial excessive earth loop impedance on final circuit

    Hi. This seems like a newbie question but please help. Received the test results with an 'excessive earth loop impedance' on one final circuit. Circuit originates with a 32A MCB and serves 10 socket points. Wiring is 2x2.5mm live, 2x2.5mm cpc. Max Zs = 0.72 Ohm. r1 (line) = 1.68, rn (neutral) =...
  22. Johnuk

    Domestic hello all i got a question on a testing question

    am looking at the question and am a bet lost now on answering it..... The maximum permissible values of earth fault loop impedance for three circuits are 1.44 Ω, 0.92 Ω and 7.67 Ω. If the measured values for these circuits are 1.25 Ω, 0.68 Ω and 6.22 Ω, determine if the measured values are...
  23. S

    ZE at board/earthing alternatives

    Hi there... Couple of questions for you experts. Still learning.....:o Been to a factory today... It has one main incoming board and 55 distributon boards scattered around there factory... They asked me to fit/wire a couple of socket outlets under one dist board. Which only uses the...
  24. V

    Testing limitations

    I cant do Ze because I can not turn off the power,it has to stay running 24/7, what do I do???
  25. brucelee

    shower question

    hi everyone i have a question on a shower circuit the ccu is a crabtree sb6000 type,tn-c-s system,100a main switch split load 6 way 4 protected by 80a 30mA rcd with shower 40a,cooker 32a not used,32a sockets for all house,16a old immersion circuit now used to supply 3 pir 500w...
  26. S

    Old problem with circuit length calcs

    Sorry to bring up an old post but im confused. I have carried out tests on a kitchen ring final wired in 2.5mm/1.5mm T&E, results as follows: r1=0.36 rn=0.34 r2=0.59 I then joined leg 1 of line conductor to leg 2 of cpc and leg 2 of line conductor to leg 1 of cpc and measured the R1+R2 at...
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