westward10

Staff member
Admin
Esteemed
Supporter
I rewired my loft three or four years ago fitting two twin 58w fluorescents. Been up and down getting Christmas stuff down, about the third time there was a pop from one of the fittings and it stopped working. Back up there today and a bigger pop from the other which took the breaker out now I have darkness, looked in both and no signs of damage or water ingress and whilst it may be a bit damp up there I never expected them both to go at virtually the same time.
 
I rewired my loft three or four years ago fitting two twin 58w fluorescents. Been up and down getting Christmas stuff down, about the third time there was a pop from one of the fittings and it stopped working. Back up there today and a bigger pop from the other which took the breaker out now I have darkness, looked in both and no signs of damage or water ingress and whilst it may be a bit damp up there I never expected them both to go at virtually the same time.
I had this a few months ago, a little furry friend had made a railway line out of the FTE.
 
There is absolutely no evidence of damage and the cables are such they are never trod on the pops definitely came from the fittings.
 
unless you want to be working over the holidays
invest in one of these?

 
What's the temperatures like in the loft. I had some that blew once when starting up from very cold. Could of just been coincidence though
 
What's the temperatures like in the loft. I had some that blew once when starting up from very cold. Could of just been coincidence though
It is very cold in the winter and by the time the tube gases had stopped swirling and got to temperature I had done what I needed to do up there.
 
https://www.researchgate.net/figure...ration-employed-in-most-of-the_fig1_261095054

It may be that the electrolytic capacitors in the electronic ballast needed reforming after a long period without being energised. Over time the oxide layer which provides some necessary insulation in the aluminimum-electrolyte rolled sandwich becomes thinner and thence unable to withstand the operating potential difference between anode and cathode. See:

Electrolytic Capacitor | Types | Capacitor Guide - https://eepower.com/capacitor-guide/types/electrolytic-capacitor/#

Upon applying power then after a long period these capacitors, especially the smoothing capacitor act like a low resistance and a large current flows; IsquaredR - in a small space equals rapid heating and a pop.

As an example here are some instructions for an ABB electronic motor drives which have not been used for a while:

https://library.e.abb.com/public/79...892e4/Guide_for_capacitor_reforming_Rev_G.pdf
 

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Green 2 Go Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses Heating 2 Go
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Advert

Daily, weekly or monthly email

Thread starter

westward10

Staff member
Admin
Esteemed
Supporter
Joined
Location
Northamptonshire
If you're a qualified, trainee, or retired electrician - Which country is it that your work will be / is / was aimed at?
United Kingdom
What type of forum member are you?
Electrical Engineer (Qualified)

Thread Information

Title
The dark loft.
Prefix
N/A
Forum
UK Electrical Forum
Start date
Last reply date
Replies
31
Unsolved
--

Advert

Thread statistics

Created
westward10,
Last reply from
marconi,
Replies
31
Views
3,543

Advert

Back
Top