Ancient Fluorescent Fittings...

[icehot]

For reasons unbeknown to me, I have just come across a fluorescent fitting, built INTO THE WALL

of my house. (sounds strange I know) - the tube has obviously seen better days (about 5 years

ago, by the look of it).

 

Now the strange thing - each end of the tube is BC (standard Bayonet) - and I want to replace the

tube. I am led to believe that fluorescent tubes with bayonet ends haven't been produced since

the early 1800s, but there are, in existence, standard G13 to Bayonet 'converters'.

 

I can't find any, so I thought I'd pass it onto you guys here - I know it's not strictly the genre of

lighting we're so used to on here, but I wondered if anyone could shed some light, or has any

experience of this old system.

 

(as it happens, all the electrics are somewhere deep in the wall - there is, literally, a switch, and

two bayonet ends on wire coming out of little holes!)

 

Any help or advice appreciated

 

Regards

[KevinE]

Can't you simply get the equivalent wattage modern tube, then swap the ends for modern ones? RS do them. I assume the tube isnt actually supported by the bayonet ends, this type were normally held in Terry Clips with the bayonet sockets on flying leads. They were popular as built-in lighting in recessed ceilings, also popular in shop fittings where the switchgear could be hidden elsewhere.

 

I actually have copious stocks of new bayonet-end tubes, however I have no idea what wattage they are without climbing up and looking, they've been in the shed for years.

 

RS page

[IRW]

...I am led to believe that fluorescent tubes with bayonet ends haven't been produced since

the early 1800s, but there are, in existence, standard G13 to Bayonet 'converters'....

 

<OT>

 

Did they actually have flourescent tubes then??

 

</OT>

[KevinE]

I'm guessing thats a typo...

 

Commercially available fluorescent fittings didnt go on sale till the late 1930's.

[icehot]

It was more sarcasm than typo.

 

I'll be putting some 'ends' onto my next order with RS - as I think the shipping for a single tube from Kevin would be prohibitative. Unless, Kevin, you happen to live in North Yorkshire??!

[adam2]

As others post, end caps to fit modern flourescent lamps are available from RS and other suppliers.

 

You will probably find however that the existing control gear wont work a modern lamp.

The existing lamp with BC ends is almost certainly 5 foot, 80 watt, T12 as this was the only rating widely sold in this style.

You may still be able to obtain these lamps, try asking local wholesalers if they have any old stock.

London Underground used these until very recently, and may still do.

 

The existing ballast may be a transformer start type, without a starter, in which case it wont run a modern T8 lamp, though it should run a 5 foot, 65/80 watt, T12 lamp with modern end caps.

 

If the existing ballast is 80 watt, then a modern 65 watt lamp will be over run, though will still last some years.

If you can obtain an old type dual rated 5foot, 65/80 watt lamp then it will be fine.

 

If the existing ballast is a switch start one (less likely) then it will work either a modern 5 foot 58 watt lamp, or an older type 5 foot 65/80 watt lamp.

An 80 watt switch start ballast will over run a 58 watt lamp.

The starter may be old type 4 pin thermal starter, rather the "modern" 2 pin glow starter. No problem if it works, but they are no longer readily available.

 

If the control gear is accesable then I would remove it and replace with a modern 5 foot, 58 watt electronic ballast for a modern 58 watt lamp.