broken light

[smartlady 1]

hi

my bathroom flush light fitting fell down from the ceiling ,bringing ,the brown and blue bulb holder wires with it, leaveing just three red wires twisted together, and three loose black wires the brown and blue wires are both conected two plastic connecters,i think that one of the black wires connect to the brown one but i don`t know which( they are not marked in any way)and the other one connects to the blue,there is also a plastic conecter without any wires attached , i do not have anway of testing the wires ,any chance of doing the job myself with a little help from you?

[verne 1]

hi smart lady, what a disaster! if you have no way of testing the wires yourself it is not going to be wise to try and do the job yourself - you wouldn't want to get this sort of job wrong, especially if you don't know much about electricity. forgive me, but if you had the first idea about it you would at least possess a means of finding a live wire...

i suggest you first think about why the fitting came down in the first place and why when it came down it managed to tear the wires out of the terminal block. obviously the fitting wasn't secure and unless the fitting is very heavy the wiring wasn't securely fitted into the terminals. when it is refitted it would be a good idea if this is sorted at the same time so it doesn't happen again.

it is usually considered best practice to ensure at least one mounting screw goes through the ceiling and into a joist in order to make a bullet proof fixing, unfortunately this does not always coincide with the desired position of the light. in this case other methods must be found to provide a firm fixing... wooden blocks in the cavity or large sheet steel washers. this can mean a visit to the roof space or lifting a floorboard in the room above.

a trick i have used a few times is to produce a large pattress from mdf in the old fashioned manner to suit the size and shape of the light fitting and provide it with a fancy moulded edge and then using no-nails adhesive and whatever screws i can to fix it to the ceiling and then in due course the light fitting can be mounted to this.

the wiring is really a job for a sparky... in the old days much use was made of junction boxes with the result that few light fittings had more than two wires to them (often plus an earth wire). in order to improve accessibility, save cost and reduce the number of connections (which in theory improves reliability) modern thinking brought the wires that would have been in the junction box to the light fitting directly. the light fitting manufacturers provided an extra few terminals and the junction box was no longer needed...

if you can visualize a cable leaving your consumer unit and visiting each light fitting in turn... you will see there must be a pair of wires (a cable) supplying the current to your light fitting and another pair leaving it which is taking the current to the next light in the daisy chain. sometimes there will be another pair providing a spur to another light if it is more convenient that way. so ignoring any earth wires there will be at least two pairs present (often more) just associated with supplying the current. next there is the switch wiring. for ordinary one way switching another pair is required and more for multiple switching... and then there will be the wires to the bulb itself which will usually amount to just another pair.

you will see that as you cannot test for voltage / current you really should not proceed further. unless you have a tremendous amount of luck it could all go horribly wrong...

[crystal_10 1]

When a single light doesn't work, the problem is almost always either the bulb, the circuit breaker (or fuse), or the switch. The first and most obvious solution is to replace the bulb with a good one and, if that doesn't work, track down the problem through a process of elimination...

1) Test the bulb and, if necessary, change it. Be sure the bulb is screwed into the socket all the way. If you put a new bulb in the socket and it still doesn't work, test the new bulb in a working socket.

2) Remove the bulb. Turn the light switch on, and check to see if the socket is receiving power by touching the two leads of a voltage tester so that one touches the brass contact at the center of the socket and the other touches the threaded metal bulb housing. If you get a reading of current, try another bulb. If you don't, go on to the next step.

3) Be sure that the circuit breaker (or fuse) for the non-working fixture has not tripped. If it has, reset the breaker or replace the fuse, and try the light again.

4) If it still doesn't work, turn off the circuit breaker that serves the non-working fixture, unscrew the cover plate from the light switch, and use a voltage tester to be sure none of the wires in the electrical box are still "hot." Then be sure the wires are securely fastened to the switch's terminals.

5) Put the cover plate back on, turn the circuit back on, and try the switch again. If it doesn't work, go on to the next step.

6) Turn the circuit back off, remove the cover plate, remove the switch and, using a multi-meter or a continuity tester, check the switch.

7) If the switch is defective, replace it with one that has the same amperage and voltage ratings. (Because switches are quite inexpensive, it isn't worth the effort to attempt repair.)

8) If the switch tests fine, remove the cover plate from the light fixture, use a voltage tester to be sure there are no hot (charged) wires in the electrical box, and then repair or replace the light fixture.

Hope it works