GEC Z8430CM

Lantern acquired in May 2004.

This lantern was used to light a section of Derby City Council's Stores Road depot. It dates from 1965 according to a date on the bowl. The replacement lantern was a WRTL MRL 6, and had a metal halide lamp fitted. Archival photographs suggest that Z8430CMs saw moderate usage around Derby, particularly on main roads around the Pear Tree and Normanton areas, where the lanterns were attached to the support poles for the overhead wiring that supplied Derby's trolleybuses, and this lantern could have been installed within the City before being re-used at the depot, particularly as the trolleybus operation ceased in 1967.

These first two pictures show sections the column and bracket that the Z8430CM was on whilst in service. Unfortunately, I didn't manage to get the image of the lantern in the reflection of the new van's window (on the left)!

From the side, the similarities to the later Z8896 side road lantern can be seen. Glass was the default bowl type, rather than polycarbonate, making this quite a heavy lantern. The bowl catch is also slightly different. The 'CM' prefix identifies this lantern as utilising a revised bowl design that was optimised for Corrected Mercury Vapour lamps; the original Z8430 having been designed for uncoated MA/V-type lamps.

The only difference in the appearance to the Z8896 is that, on top of the lantern is the addition of the GEC logo. No hole has been drilled in the canopy for a photocell as the lantern ran on a time switch.

Inside, however, the lantern is very different. Firstly, the lamp is mounted by the cable entry, rather than opposite. Also, the addition of reflector panels on either side of the lantern helps to focus the light out of the lantern. The gasket around the rim of the lantern appears to be some kind of rope - quite possibly made from that wonderful cancer-causing material known as asbestos. This may also be the material that was used to insulate the wires going to the lampholder - great! Of further note is the lamp that was fitted - this is a GEC 'Truelite' 250 Watt MBF dating from April 1978. Needless to say, by the time that the lantern was retired into the Collection, this lamp's arc tube was considerably blackened!

The bowl is offset slightly in relation to its aluminium support ring.

Just for size comparison, I put the Z8896 next to the Z8430CM. Notice that the Z8896 does not have as curved a canopy as the Z8430CM has. Maybe, then, the Z8896 is actually the larger version of the earlier design - the Z8591.

Restoration of the lantern took place on Thursday, 17th June 2005.

The lantern was mounted to an AC Ford AC872 wall bracket on Tuesday, 9th August 2005.

On Thursday, 10th November 2005, the lantern was finally able to be powered up.

Following the acquisition of a second Z8430CM in April 2009, this example was taken out of service, awaiting the day when it could return to service in some form. This day arrived nine years later, in April 2018, when it was fitted to another wall bracket.