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Fusebox - loose connection on busbar and mcb
- Thread starter mogthefrog
- Start date
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OK thats great advice.
If I could please ask another question: Do I have some time to get this seen to? I shouldnt expect the CU to blow up from overheating etc in like a couple of days?
Also, if everything goes wrong again, is it likely that this will cause a fire that will spread to the rest of the house? Or will everything be contained within the CU itself?
many thanks,
mogthefrog
If I could please ask another question: Do I have some time to get this seen to? I shouldnt expect the CU to blow up from overheating etc in like a couple of days?
Also, if everything goes wrong again, is it likely that this will cause a fire that will spread to the rest of the house? Or will everything be contained within the CU itself?
many thanks,
mogthefrog
It's hard to say, if the busbar is badly damaged then theres a chance the same thing could happen the next time you use the shower, but it might last a few days, weeks, months no-one knows.
It's just better to get things seen to before they have a chance to get worse.
The CU won't blow up from overheating, it'll get hot, some plastic will melt, some smoke will be given off and hopefully before it gets too bad your smoke alarm will sound and you can shut off the supply. If there are lots of flammable things surrounding the CU I'd move them.
It's just better to get things seen to before they have a chance to get worse.
The CU won't blow up from overheating, it'll get hot, some plastic will melt, some smoke will be given off and hopefully before it gets too bad your smoke alarm will sound and you can shut off the supply. If there are lots of flammable things surrounding the CU I'd move them.
So far everything is working OK. Ive used the shower a few times since this happened and so far all is fine. I think the flat I'm living in was built about 3 years ago and this is the first time such a thing happened, though Ive been living here for about 4 months. The electrician said that the guy who installed the CU should have checked the connections properly. I am currently looking into the documentation because I think that the electrics have to be guaranteed for a certain time (10 years I think) I need to find this out and then contact the builders who I think should be responsible for future costs. When this event happened a couple of days ago it happened during the night and the smoke detector didnt go off. I think it all happened within the Cu itself and no smoke came out of it as far as I know.
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it will only overheat while current is being drawn through a bad contact. Most likely while you are using the electric shower. I see you have your cooker and immersion heater on the non-RCD side, so on a different busbar which is not damaged.
If you have a tumble drier, washing machine or dishwasher on the RCD side, and especially if you run them all together through the same MCB, that will take quite a lot of current too. Small loads like TV and lights (usually) create very little heat. This kind of fault is much more common on electric shower circuits, as in your case, and the old busbar will have been hottest at the prong for the shower MCB so this is where it is most likely to have been damaged and give trouble again. The erosion gets worse over time
Perhaps have baths until you get it fixed?
If you have a tumble drier, washing machine or dishwasher on the RCD side, and especially if you run them all together through the same MCB, that will take quite a lot of current too. Small loads like TV and lights (usually) create very little heat. This kind of fault is much more common on electric shower circuits, as in your case, and the old busbar will have been hottest at the prong for the shower MCB so this is where it is most likely to have been damaged and give trouble again. The erosion gets worse over time
Perhaps have baths until you get it fixed?
For all I know the electrician might have replaced the busbar also. Im just not sure at all.
with regards the shower, in order to switch the shower power on there is a big red switch which has to be pressed in order to turn the power on. This is switched off after every shower and only pressed when the shower needs to be used. Does this make a difference in terms of electricity going to the shower and potentially overloading it?
I will definitely be getting this seen to. It is just that it could take a few weeks/month or so to sort out. Im concerned about safety issues int he meantime. Power cutting out I could cope with. Fire in the flat is a different proposition
with regards the shower, in order to switch the shower power on there is a big red switch which has to be pressed in order to turn the power on. This is switched off after every shower and only pressed when the shower needs to be used. Does this make a difference in terms of electricity going to the shower and potentially overloading it?
I will definitely be getting this seen to. It is just that it could take a few weeks/month or so to sort out. Im concerned about safety issues int he meantime. Power cutting out I could cope with. Fire in the flat is a different proposition
Was the isolator switched off on the night the problem first occurred?
I think so. It normally is. HOwever, the missus does leave it on quite alot when not in use. I usually switch it off. Could it be that this has had some cumulative effect which caused the incident?
Well as JohnD mentioned, overheating will only occur when current is being drawn through the dodgy contact. Since this happened during the night I'm assuming no-one was using the shower and that loading throughout the house would have been minimal?
If it wasn't for the circuits being on the RCD side I would have thought a high resistance earth path accompanied with L-E leakage but the RCD should have tripped in this event and even if it hadn't I doubt <30mA wouldn't have done that amount of damage.
Do you have the schedule of test results for the installation?
If it wasn't for the circuits being on the RCD side I would have thought a high resistance earth path accompanied with L-E leakage but the RCD should have tripped in this event and even if it hadn't I doubt <30mA wouldn't have done that amount of damage.
Do you have the schedule of test results for the installation?
Im not sure if I have what you were asking for but this is what I do have.
On the plastic cover for the CU there is a sticker that says that the date of the last inspection was 4/4/2003. The next inspection is recommended for 4/4/2013. The flat Im living in is new and I dont think it was built much before 2003.
On the plastic cover for the CU there is a sticker that says that the date of the last inspection was 4/4/2003. The next inspection is recommended for 4/4/2013. The flat Im living in is new and I dont think it was built much before 2003.
not sure if this is relevant but the mcbs are 32A mcbs.
no mention of fitting a new busbar. It is not a part I would expect wholesalers to keep in stock, probably have to be ordered from Wylex (if you write to them and say yours was damaged, you never know, they might send you a new one)mogthefrog said:
nope did tget anything like that. He wrote ont eh receipt that the work was temporary adn that further work would be required at extra cost.
Just thought of something. Would it help if I switched the shower mcb to OFF after ther shower has been used for the day? Would this reduce electricity going to it? Or are mcbs not designed to be switched on and off on a daily basis? This would be a temprary thing until I get the problem sorted out.
Just thought of something. Would it help if I switched the shower mcb to OFF after ther shower has been used for the day? Would this reduce electricity going to it? Or are mcbs not designed to be switched on and off on a daily basis? This would be a temprary thing until I get the problem sorted out.
mogthefrog said:
What company was this? Did he do any tests atall? All work should be tested and certified, even 'temporary' work.
mogthefrog said:
Switching off the MCB would stop current flowing through but there shouldn't be current flowing throug when you switch off the isolator anyway.
MCB's aren't really meant to be switched on and off on a daily basis but for a short term solution it should be ok.
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