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A circuit breaker does not work properly?

  1. Jul 21, 2015 #1
    I live in Egypt where we use 220V AC / 10 A.
    When I turn light off at a circuit breaker, all lights turn off but both mains ( hot & neutral ) become hot.
    When I test them, they both have electricity (live), so I afraid to touch them.
    I would expect that they both become neutral ... Why does that happen ? and what is the solution ?
    Thanks in advance,
  2. jcsd
  3. Jul 21, 2015 #2


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  4. Jul 21, 2015 #3
    I don’t know the exact answer, of course. However I presume in Egypt the rated system voltage is 380/220 V indeed.Most of the dwellings are single-phase supplied.

    In my opinion again, it has to be a short circuit or a large receiver in installation.

    The circuit breaker will trip for 3 times rated current in 10 seconds.

    In 10 sec. at 30 A a10 A circuit breaker could be hot.

    If the lights are off -let's take these as incandescent bulbs- it could be at least 50% drop.

    If at the end of a 100 m conductor of 1.5 mm^2 copper you'll connect a 3300 W receiver you'll get 30 A at the circuit breaker and a voltage drop of 50% [that means 110 V] for at least 10 seconds before it trips.
  5. Jul 21, 2015 #4
    Make sure that the circuit breaker box is properly grounded. If is is not the neutral wires can become "hot" due to feedback from other circuits.
  6. Jul 21, 2015 #5
    No, My house is a single-phase supplied. In Egypt, We have two mains only (hot and neutral). We don't have the third wire (ground) which is for safety.
  7. Jul 21, 2015 #6


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    You need to consult a licensed electrician to figure out your problems with your house wiring. Thread is closed.
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