Search results | Page 10

Search results

  1. Lucien Nunes

    Can I confirm how to test for and how to find a borrowed neutral?

    This N-E test stuff is all old news, see my post #19. There is unusually low insulation resistance between neutral and earth but not a short, so whilst it needs finding it's not the reason that the two neutrals show a hard short together. It might be further evidence of some cables nailed...
  2. Lucien Nunes

    Pure sine wave inverters. 12v /230v

    If the OP was serious, neither do I. Or rather, it's a common problem with a very simple solution - a 3-position DP transfer switch. The OP claimed there was no room for the switch and I appreciate that not every motorhome has a conveniently located engine room like my boat (where my ATS is)...
  3. Lucien Nunes

    Can I confirm how to test for and how to find a borrowed neutral?

    Oops I think that's a quote from my post #19!
  4. Lucien Nunes

    Pure sine wave inverters. 12v /230v

    It's the most ludicrous proposal I had seen in a long time which I suspected to be trolling and not a real thing. After a while it started to nag me that he might actually be doing this for real, so I replied. I wonder how many people have had shocks since the thread was current 2 years ago...
  5. Lucien Nunes

    Can I confirm how to test for and how to find a borrowed neutral?

    Nothing wrong with that, but I'd take advantage of the known continuity of the ring to save opening and disconnecting stuff. I would inject a current around it from a small ELV benchtop power supply that can operate in constant-current mode into a short-circuit. First I would go to the CU and...
  6. trace erroneous.png

    trace erroneous.png

    • Lucien Nunes
    • Media item
    • Comments: 0
    • Category: Electrical Videos
  7. Lucien Nunes

    Is this asbestos wire??

    It's impossible to say with 100% certainty from the appearance. Knowing the brand and age can help decide whether it is likely.
  8. Lucien Nunes

    UK Can anyone help date this cable please?

    Probably 1930s, although if it was clipped to the door frame on the surface it seems likely to have been put in after the house was completed. It looks like tinned copper 1/.044 (i.e. one strand 0.044 inches in diameter) which was the imperial forerunner of 1.0 sq mm and the only non-stranded...
  9. Lucien Nunes

    Can I confirm how to test for and how to find a borrowed neutral?

    In theory any test that can be done using load can also be done dead using resistance, and as a dead test that ought to be preferred, however the load test might involve less disturbance of the fittings. As the lighting circuit is a radial, as the load is moved away from the CU towards the...
  10. Lucien Nunes

    Can I confirm how to test for and how to find a borrowed neutral?

    The test with the CPCs disconnected would be mainly to find out whether the N-N fault is actually a manifestation of two N-E shorts, one on each circuit, linking the neutrals together via the CPCs. However, we already know that there are no solid N-E shorts, only that 0.1MΩ that drew your...
  11. Lucien Nunes

    12v Yacht Bow Thruster does not work with Victron BatteryProtect 220A

    Use the control relay to break the red lead of the thruster control harness, pin 4 on the multiplug. However, if the circuit diagram is to be believed, pin 4 is simply a permanent battery positive feed protected by a 1A self-resetting PTC 'fuse' in the thruster control box. It might therefore...
  12. Lucien Nunes

    12v Yacht Bow Thruster does not work with Victron BatteryProtect 220A

    Don't use a big contactor unless you absolutely need its function as a battery isolator. So long as you have a manual battery switch as a safety provision, then it's only performing a control function and the thruster's internal solenoids can do that. The problem with a conventional contactor is...
  13. Lucien Nunes

    12v Yacht Bow Thruster does not work with Victron BatteryProtect 220A

    First of all note Julie's comment; even if the BatteryProtect is reversed, you might get enough momentarily to just pick up the motor power solenoid, and the same if the BP is faulty or tripped. Assuming it's working and correctly oriented, as also mentioned by Julie it's important to discover...
  14. Lucien Nunes

    Ex Royal Signals Command and Control Bunker

    An ECM (earth continuity monitor) can operate in one of two directions: downstream, making sure that a connected load is getting an earth from the installation, or upstream, making sure that the installation has an earth. We seem to have both elements here. The ECM in the unit is looking for...
  15. Lucien Nunes

    Capacitor in AC circuit

    It most certainly is sinusoidal. Q=CV where C is constant. I = dQ/dt = C.dv/dt. Everybody with me so far? What does sin(x) differentiate to? And what shape is that? Please get yourself an oscilloscope, a function generator and a capacitor and satisfy yourself that this is true. I did when I...
  16. Lucien Nunes

    Shock from switch due to dampness

    There are many different plastics with very different characteristics, but electrical accessories like traditional UK light switches made of hard white 'plastic' aren't really plastic at all, but thermosetting resins with fillers (thermosets.) There are many different permutations of resins and...
  17. Lucien Nunes

    Omission of overcurrent at origin of installation?

    I think the combination of the OP's insight and the replies by @pc1966 more or less exhaust the subject. I would draw attention to the way that for meter tails, the considerations are partly electrical and partly administrative. On the one hand, the electrical situation is fairly clear...
  18. Lucien Nunes

    More on the 3 phase question.....

    As @brianmoooore and @pc1966 mentioned in the other thread, when dealing with 3-phase distribution feeding single-phase loads that can be 100% unbalanced (e.g. one 1-ph office/EVCP full load, another zero load) the worst case is always the fully unbalanced one, as we derive no benefit from...
  19. Lucien Nunes

    Wiring a relay?...................

    The WiFi relay is rated at 16A, but it will be designed for compactness and a 16A load would probably be pushing the actual relay within towards its limit. I would be interested to know how well they last when operating a 3kW immersion. Might be 100% fine and the electronics might be life...
  20. Lucien Nunes

    Icelandic Electrical Installation.

    Jordfeilvarsler? (=earth fault warning device) I don't know how they were configured other than that they tended to trip even if the fault was outside of your own property, which is one of the snags of IT supplies - an insulation fault in one causes abnormal conditions in all, as you noted...
View older results

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

YOUR Unread Posts

This website was designed, optimised and is hosted by untold.media Operating under the name Untold Media since 2001.
Back
Top