Fluorescent Tube Question.

1) nothing will change unless the tube is faulty, it will strike as before. Perhaps more or less rapidly if the two filaments are volatilizing at different rates.

2) depends how the conversion was done . If the starter has been replaced by a short, then is should work either way round. If L and N only  go to one of the lamp caps, then obviously it will only work that way, and may go bang if reversed, or nothing,,

It is a known problem hence these warning  labels are sold.

Mike

That is the worrying point Mike. The new L.E.D. tube is supplied via just two pins L for one pin and N for the other at just one end of the old fitting after conversion. .The old internals are totally disconnected in the old fitting. So just one end cap supplies L and N. SO, if the house holder takes the new L.E.D. tube down to clean it or replace it and then inserts it the wrong way round it creates a DEAD SHORT as the two dead tube pins are shorted together.

Is this a design fault?

Z.

It's probably slightly safer than the earlier design that could accept L&N from either end - the pins at one end were directly connected to the pins at the other end - so if it was inserted one end first into a live fitting the exposed pins on the other end of the tube would be live.

  - Andy.

How did you find out it creates a dead short?

The new L.E.D. tube came with no instructions at all. I had an instruction sheet from a 4ft tube though that explained that the supply is from one end only. I referred to that after having trouble with the B6 M.C.B. tripping off. The two metal dummy pins are connected together on the 5ft tube as confirmed by an Ohmeter. The feed end  is marked on the tube end but is only in small print. Having accidently fitted the tube the wrong way round I tripped off the B6 M.C.B. I think that the design of the tube is dangerous and bad. The two dummy pins could be separated and not shorted together. A very poor design. Also, it is possible to fit a new tube wrongly as the live end cap of the fitting is not identified. I prefer the new L.E.D. tubes with the replacement fused "F.S.U." These require no internal alterations of the old fitting's internal wiring.

Z.

the idea is to put L to one end, neutral to the other and short the starter

It’s a few years since I converted a fluorescent fitting to LED, the last one I did was over a Dulux Paint sign outside a former DIY shop that had become an Indian Restaurant.  

As it is a Conservation area it seemed easier to revamp the existing illuminated sign than apply for permission for a new one, but no one changed the actual sign.

Once the starter is replaced there’s nothing to control the current if someone swaps a fluorescent tube back into the fitting, so the starter really needs swapping for a fuse, which can be a fused dummy starter or a fuse in a holder within the fitting, if you can get a suitable one.

ah is that why the Indian food is so colourful?  Dulux paint....

joking aside,

I imagine that swapping it back to a florry will soon be impossible as they will not be made for all that much longer.

From 24 February 2023, the following light sources will be phased out:

• CFL, compact fluorescent tube, life time < 20.000 h

• T9 Circline lamps >10 - <15 mg mercury

From 24 August 2023, the following light sources will be phased out:

• CFL, compact fluorescent tube, life time > 20.000 h

• T5 fluorescent tubes (≤ 3 mg mercury)

• T8 fluorescent tubes (≤ 3,5 mg mercury)

From 23 February 2027, the following light sources will be phased out:

• HPS High pressure sodium lamps

• MH Metal halide lamps

Mike.

No. The instructions that I eventually found in a 4ft pack of the same maker's 5ft tube called for a single feed at one end only.

Z.

These are better.

Crompton 22 watt = 36 watt 4ft T8 LED Tube Colour 4000k Cool White Lamp 5055579302944 | eBayI

If these are the ones that I have used before they come with a dedicated fused "F.S.U". That is just a fuse and NOT a working fluorescent starter unit.

Z.