Trying to avoid unnecc rewiring!

[loumo]

Background info - the previous owner of our house decided he could rewire loads of things himself. Not well, it turns out...lol!

For a year, our upstairs light circuit worked fine. Then the circuit breaker began to trip when a light was switched on, perhaps once a week, for a few weeks. Then it utterly crashed...it tripped and it won't go back on.

No recent improvements to anything. Circuit has one hall light, one bedroom light, bathroom (3 50w halogen downlighters) and master bedroom (five 50w halogen downlighters). There was a problem with the master bedroom switch, I have changed it, and the lights worked for about ten minutes then it all crashed again.

I'm thinking we have a short circuit somewhere, and I am tracking down a multimeter to take some readings. What information can I give you guys to help you to hep me work out what to check next?

I have three little kids, one a sick baby, so this is all very much based on what little brain power I have operational...so don't assume anything, ask me everything you think of!

Thanks,
Lou.

 

[chivers67]

Power off. I'd check all the connections on the bedroom with the five downlights.

 

[seasickstevie]

Are your downlights 12v or mains?

If 12v it could be a transformer coming to the end of its life. If you can see them, look for one that's discoloured or even deformed. And have a good sniff. If one's causing trouble, it'll be the stinkyest! (is that a word?)

 

[loumo]

Ok, this is where we are now. I had previously replaced the switch in the master bedroom. Hubbie reckons the resistance int he circuit breaker changes when that switch is wired, but either way, it won't switch on.

Pulled out the master bedroom downlights. No transformers, one of them had a slightly blackened insulating cable. Taking no chances, replaced the entire thing (recessed downlight). No change to the problem.

Checked voltage across the circuit. Voltage in 2nd bedroom light fitting, controlled by switch. Same for hallway light. Voltage in switch but none of the light fittings in the master bedroom, same for bathroom. Bathroom lights have transformers on two of them, both looked fine, the third is a different fitting, and has what seems to be a fan (attached to a length of tumble dryer pipe stuff) above it, not working. The light was working fine, the fan was not.

Disconnecting the switches in the master bed and / or bathroom make no difference to the rest of the circuit. Current vague plan is to save up till we can afford to get the damn downlights removed, regular light fittings placed in both rooms and the ceilings re -plasterboarded, but that's going to be some time. Lamps till then, and showering the kids in the dark or baths at weekends during the day... Anyone any ideas on what else I could try?

 

[ColJack]

you say the breaker won't reset, yet mention voltage at various lights..
does it turn back on or not?

this switch you've changed, is it a dimmer? ( don't even get me started on putting 250W of lighting in then turning them down because it's too bright.. )..

at a guess there's a connection box above the bedroom where the old pendant has been swapped for the downlights and there's a loose connection in there..
failing that, take down the rest of the lights and check at them for loose connections..

get us pictures of inside the switches so we can see if you have loop in at the roses or the switches..

 

[loumo]

Nope, doesn't turn on. There is a v slight voltage across the switches in each room, and in the light sockets in the 2nd bedroom and hall when the switches are turned to on. (Residual power in the circuit? I dunno...) There is no voltage reading in the lights in the main bedroom or bathroom.

Yes, it was a dimmer. He fitted them everywhere he could, as many recessed downlights as he could cut chunks of ceiling out, then dimmers...why you would ever need 250W in your bedroom is beyond me in the first place, but to the go play with dimmers on it...as I said, he thought he was on some daytime tv fix it up and sell it on show, he decided he could do all sorts to the place, and in the end, he just did it all really badly!

I've taken all the downlights down and checked them over, they all seem ok in terms of wiring etc. I don't know what I can do without any power in the circuit to test things, though. Got a multimeter but it can't do v much with nothing to test...

Will try to get pics of the switches, need to use my phone, though, and it has light quality issues...master bed switch has earth wire fixed to the metal band across the back of the inset area, and the two wires running into the switch. Bathroom is a pull cord with a whole heap of stuff, I'll try to get it done tomorrow when it's light.

There are choc boxes on each downlight. It seems triple core runs to them, then the earth stops there and the wire coming from them is like coaxial, it just has the two that are going in to the lights. I did check them visually but I might check them with the multimeter and tighten up the wires...looks like another trip to the loft to inspect from all angles.

I'd love it to just be a loose wire and not something totally dismal...lol...but I'm just so lacking confidence in the previous owner's abilities to do anything right rather than slipshod...once it's daylight again, I'll go investigate further, thank you for helping! Sorry to be so girly about it all...but I'm a girl...