Fluorescent Light Problem

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Christmas day and kitchen light starts flashing on and off.
Tried another starter no cure, its a 5ft tube so I tried the tube from a very old working fitting in my garage its fatter but still bypin.
It cured my problem but its a 65watt as opposed to 58watt of the original, when I purchase a replacement am I ok with a larger wattage than the original will it damage the fitting, and if ok how powerful could I go please.
 
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Christmas day and kitchen light starts flashing on and off.
Tried another starter no cure, its a 5ft tube so I tried the tube from a very old working fitting in my garage its fatter but still bypin.
It cured my problem but its a 65watt as opposed to 58watt of the original, when I purchase a replacement am I ok with a larger wattage than the original will it damage the fitting, and if ok how powerful could I go please.

No problem, youve probably swapped out a T8 tube 25mm for an old T12 tube 38mm, the pin centres are the same.


Smaller tubes are more efficient, more light for less watts.
 
Yep as above, 58w T8 or 65w T12 will work fine. You will be buying a 58w T8 tube seeing as T12's are obsolete and are (generally) no brighter despite the higher wattage.

Get a colour 830 tube if you want warm white or 840 if you want a fairly neutral cooler white, I advise against 'daylight' 860/865 tubes as they're a yukky blueish colour. I advise buying an electronic starter too, these can double the life of the tube and will mean the tube starts up first time without that annoying repeated flashing. See item 153453947627 on eBay for the starter. They also last for many years unlike traditional starters that often need changing regularly.
 
You will not be able to buy a 65 W tube any more, the ballast does two things, gives a voltage boost to start the tube, and limits current once running. A 240 volt ballast will have a problem starting a 58W tube, a 220 volt ballast will likely work OK.

Today we use electronic ballast units and voltage does not matter that much, but old wire wound it may say 58W but if volts are a little high can draw 90W.
 
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A 240 volt ballast will have a problem starting a 58W tube, a 220 volt ballast will likely work OK.
A 240v ballast on a 240v supply will work absolutely fine with a 58w / T8 tube, it's literally what they're designed to do. If you live in an area with lower than usual voltage (say 230v), the tube may be under-driven and take some effort to strike up. Generally in the UK you should not be seeing voltage as low as 220v, so there should never be a need to use such a ballast. 230v ballasts are an option if you happen to live in an area with the unusual 230v supply voltage.

Today we use electronic ballast units and voltage does not matter that much, but old wire wound it may say 58W but if volts are a little high can draw 90W.
It would be unusual to see 90w power draw on a 58w circuit, unless you were using a 220 or 230v ballast on a 240v supply that actually sits at the higher voltage limit of around 250v, in that case the tube will be over-driven and the ballast will run very hot. In my own man cave I'm using 58w T8 tubes on 240v ballasts with a supply voltage usually around 251v, and power consumption of each fitting is about 68-70w.

To conclude, yes wire wound ballasts being an inductive load are sensitive to voltage and you should always use one with a rated voltage that's as close as possible to your actual supply voltage.
 
I had a boss who thought lighting some tunnels it would be better to use 110 volt fluorescent lights rather than the normal festoon of 60W bulbs, the supplies were protected by 16A MCB's so quick calculation 0.5A each slightly over 0.53 but 25 units should used just over 13A (13.18) so around 3 amp to spare. So they were made up, and plugged in.

However very quickly they failed, so now it was find out why.

Clamp on ammeter showed they were drawing nearly 25 amp, quick cure was disconnect some, but then find out why using so much.

So back in the workshop one lamp opened, and it was found to be a standard 230 volt unit plus an auto transformer not quite centre tapped there was a 110 and a 127 volt winding, supply on the 110 volt winding using 0.8A if the capacitor was disconnected jumped to 1.1A, move the supply to the 127 volt winding and the current dropped to around 0.6A. That would mean 15A draw for 25 units, so within the limits, so each unit opened and the tapping swapped, found the last few would then not start so last 4 returned to 110 volt winding. Measured total then still under 16 amp so they then worked as we had expected.

This was early 1990's and after this I was careful to measure power used with lighting, if high, it normally mean the power factor capacitors had failed, however then the electronic high frequency ballast slowly replaced the old wire wound and they transformed the fluorescent light, increasing output, increasing tube life, and auto adjusting to supply voltage, some could work 185 to 250 volt, only problem was a faulty tube could damage the ballast so tubes needed changing straight away, before that is was common to program tube changes, and every two to five years all tubes were changed if needed changing or not, but with electronic ballast that would likely mean many new ballasts needed fitting as well.

So now to my own home, kitchen had a 65W fluorescent likely one that was changed some where my father-in-law or I worked and brought home as good enough for kitchen, a tube would last around 5 years, then the supply dried up, so fitted 58W tubes, these did not last as long, maybe 2 years each, but OK. And then after a load of solar panels fitted local found only lasting 3 months or so, actually found an old fat tube at Wickes that lasted well around 2 years or so, but then could not find a replacement.

When the official voltage dropped from 240 to 230 there was in real terms no change, often voltage was around 250 volt, however when solar panels came out they require an auto shut down if the volts go above 253 or below 216.2 to ensure they don't electrocute people working on what should be a dead line. So the local voltage dropped, to 230 volt, I assume to stop solar panels tripping out, it was when the solar panels appeared that the fluorescent lights started to have problems striking.

So I had two options, remove the whole fitting, replace either whole fitting or change the wire wound ballast for an electronic one, and replace, or fit a LED tube. The LED tube would work simply by swapping the starter for fuse supplied with new tube, however the old ballast becomes a resistor and means the LED is inefficient so removing the ballast was better option, not physical removed just electrical, the LED tube was just 24 watt, and the lumen output dropped from around 5600 to 2400 but it was bright enough, however it was the shortest any LED lamp has lasted and within 18 months needed replacing, this time 22W and still working, however hardly used as we have moved house and it stands empty most of the time.

Had we not decided to sell the house I would fit an electronic HF fitting.

I am sure by now @polomints will have got a new 58W tube for kitchen and moved the old 65W tube back to garage, and likely it will work like that for years to come, as to replacing with electronic or LED not sure if saving enough to be worth the effort? I was rather impressed with LED lighting to start with, however it seems to make it seem brighter the LED's are pulsed, but when it comes to read using LED lighting I find not bright enough.

For lights using bulbs I love LED lights, for lights using tubes not convinced yet.
 

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