A complex problem?

[PaulMac07]

Hi all, Newbie here seeking help with a lighting problem.

A couple of weeks ago I noticed that the lamps and ceiling lights tended to flicker much more than before. Today when my wife came home we had a very short power outage, which lasted for 2 or 3 minutes. She checked with the neighbours, but no-one else had a problem. The power restored itself, no circuits had tripped.

When I got home I tried to load up the system to see if I could make the flickering worse, or if I could find a hot spot on the CU. The lights didn't flicker at all, but the lights MCB tripped after about 10 minutes. The MCB was very slightly warmer than the others. The MCB reset no problem

Now, I suspect there may be a problem with the MCB connection wiring, or maybe an appliance or ground leak. But none of this explains the short outage?

Very confused, and any help would be much appreciated.

Regards,

Paul


P.S. Pretty sure this is coincidental, but my 9kw shower decided to gradually die over the past day or two. Probably not connected, but I thought it was worth mentioning.

 

[securespark]

You would do well to check all connections in the consumer unit, but this needs great care & the right tools.

 

[sparkyspike]

Your neighbours could be on a separate phase to you, so you could still have experienced a supply problem, which could have led to lights flickering followed by a power cut. Regarding your lighting MCB tripping, what did you do to load it up?

 

[ricicle]

Do not try this unless you feel 100% confident/competant to do it.The CU needs to be isolated at the mainswitch but the incoming terminals on the mainswitch will still be live.It is also worth checking that the MCB is located correctly on the busbar.Again if in doubt seek help from a competant electrician

 

[RF Lighting]

Is the problem just in one part of your house or is it everywhere?

ie, usptairs is OK, but downstairs flickers?

 

[JohnD]

As ricicle mentions, occasionally, you find in a CU that one or more cables or busbar prongs has been poked into the bottom of an isolator or MCB which has then been tightened up... but it's been poked into the wrong side of the gripper, so instead of being gripped, it just makes a loose contact. You may be able to observe this by signs of overheating discolouration on the loose cable or prong; or by squinting up with a torch from underneath. You might hear the bad contact fizzing under load.

Be sure to turn off the main switch before removing the cover to check, and call in a recommended local electrician if you are not competent to do it yourself.

 

[PaulMac07]

Thanks guys, your help is really appreciated.

The lights have been flickering for a few weeks, so I'd be surprised if the outage wasn't in some way connected.

I am pretty confident with electricity (although I'm a joiner...), and feel fine about isolating the CU and checking the connections, I have a good set of insulated screwdrivers, and my wife is a quick learner and follows simple instructions quite well (only kidding).

The light flicker is all over the house, but I have a feeling that all light circuits are fed from one MCB.

Could it be a supply quality problem at all?

 

[PaulMac07]

Regarding your lighting MCB tripping, what did you do to load it up?

Basically switched on all the lights, kettle, Microwave etc.

 

[RF Lighting]

It is possible that it is a supply problem, but it is more commonly on the consumers side of things.

I have seen a failed connection on the incommng side of a DNO cutout, but I would think the CU is the first place to look.

 

[sparkyspike]

Do you have any lamps plugged into a ring circuit? If they flicker too then your problem could be supply (contact your distributor) or your consumer unit connections.

 

[PaulMac07]

Do you have any lamps plugged into a ring circuit? If they flicker too then your problem could be supply (contact your distributor) or your consumer unit connections.

Yes, both livingroom lamps are connected to the ring main.

 

[PaulMac07]

My Missus reckons that there may be a ground leak or some other electrical problem coming from our faulty shower that's causing fluctuations in the rest of the house.

Please don't tell me she has a point...

 

[sparkyspike]

If you've checked that the MCBs and the busbar and neutral bar are all connected tightly, as well as the main tails then you could have a supply fault. Is anyone down the road experiencing any problems?

 

[sparkyspike]

She may have a point...

 

[RF Lighting]

I suppose a loose connection on a heavy load such as a shower could cause the lights to flicker, but this would only occour when the shower is in use.