Lights flickering

[Jel]

We changed a consumer unit around 8 months ago, and the tenants are saying that the lights in the house all sort of flicker at the same time.
They say they think it started around the same time as we changed CU. All
The connections are tight, and there are no dimmers, anyone know what might be causing it, as they think it will damaged there computers?

 

[telectrix]

could it be at a time when all the neighbours start cooking the tea? volt drop on supply.

 

[Geoff]

Most probably the Meter tails are too small to cope with the increased load.
It's the usual story, New CU = more circuits = more load.

 

[Rockingit]

Most probably the Meter tails are too small to cope with the increased load.
It's the usual story, New CU = more circuits = more load.

Really?? New CU = more circuits, yes. More load?? Did they buy a second or third kettle to celebrate your work?

I would suggest that on a domestic level, loads are decreasing. Low energy lights, digital electronics etc etc. What is the heaviest load in your house outside the kitchen (apart from an immersion/shower etc)....probably a hair dryer.

 

[Coffeemad]

I've had this before when all my terminations where tight, the bus bar pin was outside of the terminal on the MCB. With modern boards and having to take the busbar off completely to add and remove MCB's, I can see this becoming more of a problem. I use a small plastic mirror just as a quick doubel check to make sure they are all in within the terminal

 

[Geoff]

Fair point Rockingit!! Just trying to help!!! But I have come across this before mainly with replaced showers in all fairness!
Could be a Loose Neutral bar connection, They are often overlooked because they're factory tightend!!!

 

[telectrix]

had that myself once or twice. wylex are ,IMO, the worst. found that if you push down on the top of the terminal screw after making sure it's well backed of, you usually get em in right. like the idea of the mirror though.

 

[Darkwood]

Yes in agreement with a few posts already, the cheaper mcb brands dont have a blocking strip to stop the busbar copper stub ending up on wrong side of the clamp and you end up tightening the clamp closed empty with the stub resting on the back, its usually a visual inspection just to see if this has happened, found many a cooked mcb due to this with the heat generated. If its not this its a good all round tip to check after fitting mcb's etc anyway.

 

[Jel]

I've had this before when all my terminations where tight, the bus bar pin was outside of the terminal on the MCB. With modern boards and having to take the busbar off completely to add and remove MCB's, I can see this becoming more of a problem. I use a small plastic mirror just as a quick doubel check to make sure they are all in within the terminal

Oh yes it is probably this. I had a problem with a shower about 4 years ago completely forgot about this!

 

[sparky692]

Just gotta tell you about my flickering lights. About 6 years ago , a friend of mine asked me to look at her mums new house that she she moved in to on the Friday. It was Saturday and she said the lights upstairs in the bedroom flickered. I decided as it was Down-lighters i would pop over ,in case.Glad i did. Went straight up stairs and sure enough The lights were flickering. Look up to notice a small brown stain on the ceiling not near a fitting. MMM. lets pop in to the loft and have a look . don't like that. As i opened up the loft hatch which was pretty tight, i could smell the burning wood. The loft was smouldering away slowly. As i got up into the loft with my large torch, the main 6x 2 beam holding the loft up had burnt away. told her straight away to call the fire brigade. This had burnt away most of the roof trusses in a 5ft area. and the FB wondered how it was still up , as it must have been smouldering for weeks. Big problem is as fresh air hit the loft space , it ignited and started to flare up . loft hatch down and get down stairs double quick meethinks. Anyway . turned out the guy who owned it previously was a plasterer who thought he could wire. When i carried out a PIR on the house , i basically condemmed it . wanted to sue someone but she had bought it Sold as seen. so no come backs even to the estate agent . It got rewired before she moved back in after the insurance company builders had done the loft /roof etc. As it happens i got a good lead from them and am still doing all there electrical work . something good came out of it .
Sorry its long .
sparky 692

 

[Jel]

Damn that is scary. Stick to what you know! There are way to many other tradesmen that are not electricians, i.e a kitchen fitter, but them seem to think they can do electrics, but from the work i have been, they should clearly just stick to what they are trained to do!

 

[sparky692]

Lol. What your saying about kitchen fitters , there the worst. Got a KF recently , decided to alter my ring in a island and in doing so opened up the ring. . His reply to . W*F are you doing , you cant alter anything without consulting me first, ...Ohh thats ok i do lectrix... we do it all the time./.. Help ... how many more around ??

 

[GLENNSPARK]

I've had this before when all my terminations where tight, the bus bar pin was outside of the terminal on the MCB. With modern boards and having to take the busbar off completely to add and remove MCB's, I can see this becoming more of a problem. I use a small plastic mirror just as a quick doubel check to make sure they are all in within the terminal

Yep but its a silly and careless "fault" this though innit......If folk UNSCREWED the terminals fully firsthand...then this problem wouldn`t arrise now would it?....just bone-idleness to me this...as in "I cant be ar$ed to use a modulo driver right".............

 

[Rockingit]

talking of drivers in MCB terminals - found this brilliant torque screwdriver at one of my wholesalers the other week. A Kewtek, takes any standard size hex screw bit and adjusted with an allen key. Only £25 which I thought was a bargain by comparison with others I've seen.

 

[Darkwood]

Yep but its a silly and careless "fault" this though innit......If folk UNSCREWED the terminals fully firsthand...then this problem wouldn`t arrise now would it?....just bone-idleness to me this...as in "I cant be ar$ed to use a modulo driver right".............

, would disagree here because on some brands of mcb's(cheaper crap) if you fully open the clamp then tilt the mcb backwards and forwards the clamps will loosly slide open and closed and to fit on din'-mount its common to tilt forward thus closing clamp before you realise it, i have issues with this design and think clamps should be force action open and close via the grub-screw then this would have saved the industry a mint, as its usually the sparky that has to foot the return and repair but unless your aware of the issue its an easy trap to fall into.

 

[Globe Jockeys]

I just added a new page to my site about cause of flickering light, feel free to use the page for reference if you want to explain to any clients.

Get them to read it themselves, and save you the trouble of explaining some of the simple problems to them.
Don't worry I won't steal your clients (unless they pay me the flights from Sydney to Heathrow )

 

[Midwest]

talking of drivers in MCB terminals - found this brilliant torque screwdriver at one of my wholesalers the other week. A Kewtek, takes any standard size hex screw bit and adjusted with an allen key. Only £25 which I thought was a bargain by comparison with others I've seen.

Can you give us some more details about torque screwdriver.

 

[MarkieSparkie]

Can you give us some more details about torque screwdriver.

The price quoted in the link is the full trade exVAT price, you will get a significantly better price from your electrical wholesaler, hopefully as good as Rockingit got.

Torque Screwdriver

 

[Moses]

I've had this before when all my terminations where tight, the bus bar pin was outside of the terminal on the MCB. With modern boards and having to take the busbar off completely to add and remove MCB's, I can see this becoming more of a problem. I use a small plastic mirror just as a quick doubel check to make sure they are all in within the terminal

Been there done that!!!

 

[Moses]

, would disagree here because on some brands of mcb's(cheaper crap) if you fully open the clamp then tilt the mcb backwards and forwards the clamps will loosly slide open and closed and to fit on din'-mount its common to tilt forward thus closing clamp before you realise it, i have issues with this design and think clamps should be force action open and close via the grub-screw then this would have saved the industry a mint, as its usually the sparky that has to foot the return and repair but unless your aware of the issue its an easy trap to fall into.

I agree

I think that the screw terminal could be designed much better, may be spring loaded.

 

[GLENNSPARK]

I've had this before when all my terminations where tight, the bus bar pin was outside of the terminal on the MCB. With modern boards and having to take the busbar off completely to add and remove MCB's, I can see this becoming more of a problem. I use a small plastic mirror just as a quick doubel check to make sure they are all in within the terminal

unscrew terminations fully before inserting busbar....no probs then...

 

[GLENNSPARK]

I agree

I think that the screw terminal could be designed much better, may be spring loaded.

eh?....just push the screw in fully with the driver.....

 

[Moses]

Seen low energy lamps flickering even when switched off.

Why?

 

[Darkwood]

eh?....just push the screw in fully with the driver.....

My point to which he replied was its ok giving opinion when you are aware of the issue, but college dont tell you that sometimes after fully opening the screw clamp by tilting it it falls closed and allows the pin to sit at the back of the clamp, i use brands that have a pin shield at the rear to stop this happening so a design is out there and shouldn't be too hard to adapt to on any make of mcb, and yes your right holding it in with a driver does the job while you fit it but only if its happened to you before would you be aware of this, i put my hands up and say many yrs i fell foul and mcb overheated but never since.
manufacturers of mcb's have to follow relevent BS standards and i for one think that this should be addressed in them as many brands have seen fit to rectify this issue off their own backs.

 

[Darkwood]

Seen low energy lamps flickering even when switched off.

Why?

Normally effects LEDS and CFL's its relating to induction which has enough power to charge up the capacitive side of the electronics, usual suspect maybe strappers on 2ways and less common feed and sw in same cable, it can be overcome by fitting a suppressor will cure this but also double check earth is connected properly as this will reduce the effect.