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markandkath1 · Joined: 08 Nov 2004 Posts: 4 Location: flintshire

Hi there,
I am in desperate need of advice, before I pull my hair out (what little I have left).
In my garage I have 2 flurescent lights connected by a two way switch, One switch by the main door then a second switch by the side door, the second switch by the side door keeps on blowing fuses but it is not consistently every time I use the lights,
sometimes the lights work for weeks, I thought it may be damp but they blew in the summer, I first thought it was the switch so I bought a new one and carefully checked the wiring before replacing the switch only to find a week or so later it blew another fuse, the strange thing is that it does not always blow the fuse when I switch the lights on , today it has blown twice as I have turned the lights off. the main switch does not seem to blow fuses at all, the fuse is a 5amp.
many thanks, MARK.

markandkath1 · Joined: 08 Nov 2004 Posts: 4 Location: flintshire

In regards to my earlier post I forgot to state that from the fuse box the power also goes to another switch controlling a security light , the fuses have been blowing day or night.

vince knight · Posted: Mon Nov 08, 2004 5:22 pm Post subject:

What are the ratings of the fittings?

Sounds like either a cruched or trapped cable or the ballast unit in the fitting is suspect.

Vince

b · Posted: Mon Nov 08, 2004 5:34 pm Post subject:

It could be the original 2nd switch was improperly wired... then when new switch was installed it was wired like the old one so the problem still exists. If the switch is not wired right it could make a short circuit and blow the fuse... which is what it is supposed to do in that circumstance.
b

markandkath1 · Joined: 08 Nov 2004 Posts: 4 Location: flintshire

I have just checked the fitting ratings and they are 240 volt 50 hz, 40 watt 0.43 A or 2 x 20 watt 0.41 A. the tubes are 40 watts, There does not seem to be any sign of a damaged cable, my theory was that the security light that uses the same 5 amp fuse may be causing the overload and so when I switch on or off the flurescent lights it blows a fuse, would it be safe to increase the fuse rating to see if this is the problem.

vince knight · Posted: Wed Nov 10, 2004 6:52 pm Post subject:

What size is the security light?
If it is 500w then it is only a 2 amp load, there is no way that adding two fittings would overload a 5 amp fuse without there being an intermitant fault. My guess is still one of the ballast control units is faulty.
Do not uprate the fuse, it is going for a reason.

Vince Confused

markandkath1 · Joined: 08 Nov 2004 Posts: 4 Location: flintshire

Thanks for your help I agree, I thought the security light would have been a higher ampage, having just seen the price of ballast units I would be just as well changing both, if I bought a higher wattage ballast unit would this give me more light if I increased the tubes also, and do the higher wattage ballast units fit in the fittings, I am so pleased I discovered this website I can see it will be very usefull for all sorts of problems, many thanks, Mark.

vince knight · Posted: Thu Nov 11, 2004 9:15 am Post subject:

It would be cheaper and easyer to change both fittings completely, as a 5foot single cost less than £10 in a electrical wholesalers.

Have fun and be safe

Vince Very Happy