One for the electricians

You don't give enough info to answer the question. There were other nonelectronic ballast types than switchstart.

If you like the fitting you could always hide LED tape behind the tube so it looks the same.

Did you check the Ebrite worked when you bought it? (It's advice I don't always follow but checking that stuff ain't DOA avoids the uncertainty when you come to use it that and nowt works.)

If not then yes, I think it cd be the separate control gear that DD lamps have.

Sorry:-) The original fitting documentation is long gone. Simple D type, ceiling mounted, bathroom rated.

Hmm. I have never used LED tape and wonder if it responds kindly to zig-zag folding.

Sorry, that last sentence was f****ng useless. I meant, if you didn't check it then it could be either the Bell is duff or the lamp has another fault, which cd be the control gear.

Or of course, you did check the Bell and it worked but it's decided not to work now when you need it.

No. I don't even remember buying it!

The Bell site does not recognise the item so no help there. I'll see if the replacement from CPC works before attempting anything clever. Reading room lighting is important:-)

You can buy LED replacements for circular fluorescent tubes. If they have electronic control gear, the LED can just plug straight in. That will probably be what I do when the one in my bathroom eventually fails.

D type?

zigzag??

You don't give us anything to give any idea of whether the fault is in the tube, ballast or wiring. I can't diagnose anything from here.

Hmm. Things have moved on a bit as at switch on (with the original black ended tube fitted) it is now occasionally pulling out a 30mA RCD. Fortunately we do have other bathrooms:-)

Circular fitting with the tube in the shape of a D.

Round fitting.

The original tube appeared to be reaching end of life, dim at switch on, brightening with time. Ends blackened on inspection.

What I thought was an identical replacement tube, same rating, same connection etc. did not work.

It is a mighty coincidence that the electronic starter should die when you changed the tube My first test would be insert original tube, if it lights then the problems in the new tube, if nothing at all happens its the ballast itself, whatever it is. I can recall, many moons ago Woolworths did a range of these lights, both circular and normal, or so we thought, but one could never see a choke or anything other than a starter inside them. Put an ordinary tube in and nothing happened.These devices were also extremely sensitive to cold temperatures and would flash in a cold garage. I never did get to the bottom of how the striking voltage was provided without any kind of wound component.they were very lightweight. Brian

But did the old one still work, or was it the power supply ballast in the fitting that mysteriously went, only inserting the old tube can tell you, It could be as simple as dodgy connections if its all been up there for a while. Brian

In message <tdcv99$3hurh$ snipped-for-privacy@dont-email.me, Brian Gaff snipped-for-privacy@gmail.com writes

Reading room lighting is restored.

A replacement tube fixed the issues.

Why a dying tube should pull out a 30mA RCD is outside my knowledge.

I've also known a power correction capacitor to reliably take out a RCD. I guess some RCDs struggle with fast edges imposed on their internal electronics. One leg responds faster than the other imposing a perceived imbalance.

Why not replace with an LED tube?

I had a look before ordering the fluorescent. Plenty with 2 pin circumferential sockets but none found with the 4 pin DD mount/connector. Also only 50% light output cf the original.

There is a reason for that.

All the light is aimed downwards (assuming ceiling mount)

Ok. I would still have had to secure the new lamp and bodge a connection.

I wasn't swamped with similar looking bulkhead units although I may have discounted some on a lower lumen output basis.

Job for next time it fails! I'll be 82 or so!

Circular tubes were never D shaped afaik, so I'm guessing you mean the 2D ones.

Given the persistent and almost complete lack of info I can only conclude you aren't interested in solving the problem.

I thought Adam had in mind one you just plug in like a 2D CFL - eg

Now you tell me! The 4 pin 2D is only £5.90 and 1500 lumens.