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  1. L

    Burned wires on resistance faston connection on professional Coffe machine

    Hi all I have a professional coffe machine working at 220 V and it currently drain about 2,5 kW of power. I have made this simple and horrible schematic here just to explain how it works: Some time ago I changed the fastons on the resistance from brass faston to stainless steel faston and some...
  2. eletric

    Grounding Rod Resistance

    Now I understand why so many people in US have stories of computers blowing up during thunder storms. This is a pretty dumb rule for ground electrodes: If the resistance is over 25 ohms for an electrode, the code requires that an additional electrode be installed at least 6 feet (1829 mm) away...
  3. P

    Can earth electrode resistance values be too good/artefactual?

    Hi all, Would like some advice on the below. Context: Rural French domestic installation TT system Earth rod is situated inside the property, buried in the concrete subfloor Distribution transformer (overhead supply) is very close, on a pole approx 40 metres from the property I did some 3...
  4. R

    Do dimmers interfere with resistance testing

    I just built one of those steampunk pipe lamps. I was assembling and testing connections via resistance and a multi meter. Everything went well until I added the rotary dimmer switch. I lost all continuity. After some fussing, I loosely assembled the lamp and plugged it in. Don't worry I checked...
  5. Calebp43

    Insulation resistance confusion

    Been to a fault finding job and lights where tripping the rcbo. After further investigation we found that it was a blue strapper cable (old wiring) from one switch to another using 3 core. Let's call this cable 1. After hacking some of the cable out the wall we found that the other flat t and e...
  6. K

    How does Touch voltage work without RCD protection

    Hi everyone I asked my assessor about touch voltage and he was not keen on explaining properly and gave me a rough answer which made me think probably he was not sure himself or was hiding it. basically my understanding is afcourse that how 30mA RCD works to limit touch voltage to 50V is by...
  7. W

    Insulation resistance query

    Was testing a 3 phase DB for storage heating. While testing I noticed I was getting continuity between 2 of the circuits, which were on separate phases. Each storage heater has its own 20A radial, and when doing an insulation resistance test between 2 of the circuits I get a reading of 0.00...
  8. S

    Resistance in loom wires

    Hello. I am looking into the wiring loom of my 53 year old car and the fitness of the wires and connectors within. I have the two part loom that runs from the rear lights to the fuses under the bonnet out, and have been measuring the resistance of each line. Question is; what would be considered...
  9. J

    basic 3 core wire water resistance

    Dear Electric forum members ,Thankyou for reading this question maybe someone can help or point me in the right direction,I have been recently flooded and had water under my floor boards which covered some of the electric cables on the downstairs socket ring ,the cables were sitting in the water...
  10. UnderstandingElectrics

    TN-C-S supply, shocks from earthed sink, latest test from landlord 200Mohm resistance between E/N

    TN-C-S supply, shocks/tingles from earthed sink. Latest NICEIC test (2017) from landlord shows 200Mohm resistance between E and N As above, do I have a floating neutral, is this causing a leak from N, via bonding on sink to true earth (solid kitchen floor)?
  11. E

    Winding resistance tolerances in three phase motors

    Hi guys, Is there a standard tolerance percentage that should be followed when checking the winding resistance of each coil on a three phase electrical motor? The general rule of thumb I followed when measuring winding resistance was that each phase winding had to be identical or close to...
  12. P

    Insulation resistance of Pink Fibre

    Hi there, Does any one know what kind of insulation resistance to expect for pink fibre wall/ceiling insulation? I'm trying to figure out if the cheap insulation meter I have is actually giving me a reasonable answer. here's a bit of background: I have a GFCI mounted in an electrical panel...
  13. D

    How do you disconnect neon lights in sockets while doing insulation resistance test.

    Hello everyone, I was just wondering how do you disconnect neon lights from socket outlets when doing insulation resistance test, as this will effect the readings, thanks.
  14. dokkan1080

    Main Earthing conductor max resistance?

    I know main bonding to water and gas need to be 0.05 ohms But what about the main earthing conductor? Does it have a maximum resistance value from MET to the CU?
  15. C

    Parallel Arc Fault Resistance Found to be 0.03 Ohms

    Page 337 cites UL testing, where arc resistance was found to be only 30 milliohms: https://www.nfpa.org/assets/files/AboutTheCodes/70/70_A2022_NEC_P02_FD_PIReport_1of2_rev.pdf (You may need to sign in to view, its free) Anyway, here is the value and equation as dervied from UL: The...
  16. E

    Resistance loads

    I’m having a mind blank. If there is no load in a circuit e.g L-N was bridged at a light. Then there would be a high fault current. What if there is only one light or load on a circuit with a low resistance. Is there a minimum load resistance needed in a circuit?
  17. B

    UK Insulation resistance whole board.

    Hi all. Changing a CU in an ex-council flat, pme system, no RCD's, and initially tried to IR test whole board L/N joined to earth, got a reading of 0.28 Ohms. Then did each circuit individually (2 X RFC, 2 X lights, 1 X cooker), L/N joined to the circuit's CPC, and got between 0.25 and 0.30...
  18. H

    how would i calculate resistance using Vcc, input impedance and logic-high threshold?

  19. KeenPensioner

    Insulation Resistance zero Ohms

    Hi all. As I've said before, I'm not an electrician but an adult learner. I have a second hand Fluke 1653B MFT which is out of calibration but I use a CalCard to see how far out it is and it's not too bad. I've watched a thousand videos on EICRs etc and just want to increase my knowledge - if...
  20. timhoward

    Insulation resistance difference both ends of ring final cct

    Initial fault was RCD tripping, narrowed down to a ring final cct. IR tests on that cct with all loads removed were showing almost zero between neutral and cpc. So I broke the ring apart and eventually found the nail through a cable, and got that all sorted. Now its testing ok in as much as...
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