Unknown Fluorescent Fitting

Acquired in April 2021.

This fitting was recovered from a garage that was being rewired, and was no longer required, as new weatherproof battens were installed instead. Whether this fitting was purchased and installed specifically for use in the garage, or whether it was removed from somewhere else and installed second-hand is unknown, but it is in reasonable condition - surface rust exists on the steel bodywork, owing to the damp and draughty atmosphere within the garage, but other than that, the fitting is complete. Whereas this version is 5 ft (1500 mm) in length, examples of the same type (albeit, in 8 ft (2400 mm) length) were used to illuminate the main hall of my primary school.

The batten is supplied with a removable translucent plastic diffuser - this hooks onto the fitting body, but the fit is not very exact, and the diffuser can detach quite easily. For this reason, towards the end of my time at primary school, cable ties had been wrapped around the remaining fittings that retained their diffusers, in order to prevent them from detaching and falling onto any unsuspecting person below.

The hole in the casing that would ordinarily be the location of the starter switch is plugged in this example - the fitting is still switch-start, but the starter is housed within the fitting itself, making replacing the component a more complicated operation.

The diffuser is square-based, although a tapered diffuser was available as an alternative option.

Grey plastic end caps clip on to the ends of the diffuser - their purpose is more aesthetic than functionality, although they probably help to reduce the amount of dirt that gathers in the diffuser. Here, the circular mark in the bodywork is an unused 20 mm cable entry hole - this could be knocked out if cables (or conduit) needed to be passed through this end of the fitting.

The clips are slightly sprung, and grip the diffuser in the middle of both vertical sides.

With the diffuser removed, a rather worn 65 Watt T12 lamp becomes visible.

The lamp is made by Atlas / Thorn, but is branded with their Omega marque. I think that the date code is a year ending in a 3 or 8 (single dot above 'Made in Gt. Britain'), and as there is a dash next to the year code, the month (three dots below '65 / 80 W') could be July. The single dot above the Omega logo then suggests that it was made in the first week of this month. Thus, going on the age of the fitting, and assuming that this lamp is original, I would guess that the lamp was made in early July 1973 or 1978. As the lamp in a second fitting removed from the same garage was a GEC product, with date code 'KA' (January 1978), the latter seems more likely.

With the lamp also now removed, the two plates that allow the diffuser to hook into place are seen.

The lampholders are trapezium-shaped, with the text between the reflector and lamp pin connections being:

Type A314

2 A 250 V

Made in England

Loosening two slotted cheese head screws allows the diffuser hooks to be removed (in the cases when the fitting would be run without the diffuser), followed by the reflector. Interestingly, both items keyhole to the screws (useful when working on the fitting at height) but the keyhole slots are inversed, meaning that the whole reflector wouldn't have to be removed with the hooks. Lengths of tape used to tidy the internal wiring now hang loosely inside the channel - their adhesive properties long since having gone.

A Smart & Brown 65UC-69406/4P ballast runs the lamp. The starter is visible here too; lengths of wire twisted around its terminals connect it into the circuit in a rather crude way - I wonder why a proper starter socket was not employed. No capacitor exists, although an in-line fuse can be seen to the left of the starter.

The inside of the blanked-off starter hole.

Thorn Diffusalux | Atlas Arrowslim

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