Physical description
Set of four Polaroid prints of a Mercury Arc rectified bulb. One photo has written on rear "Hewittic Rectifiers type 500/6".
Image i4 has a person standing alongside. See Inscriptions.
Craig Tooke, formally of Yarra Trams substations advised 12/8/2020 by email to Warren Doubleday.
"An interesting photo.
I don’t know who the person in the photo is. More than likely the bulb in from an industrial installation such as mine etc. and not tram or train.
The reason is that only Melbourne trams has Hackbridge Hewittic rectifiers that were used for traction. There was three sets of bulbs installed at West Brunswick, Deepdene and Preston.
West Brunswick is definitely still in existence and probably Deepdene is still in existence as the old substation was abandoned intact and just left intact.
Preston of course has gone and was removed as part of the work done at PWS.
Another clue is the number 500/6 which means it was from a 500 kW – 6 bulb unit. The traction units were all in multiples of 150 kW per bulb i.e. the tramway ones were 600 kW rated.
The number "40246" is the bulb serial number. Each bulb manufactured had an individual serial number. Interesting the bulbs at Brisbane Tram Museum have the following serial numbers to the ones that were at Essendon tram sub. The bulbs at Essendon of course are now up at Brisbane as spares."
Inscriptions & markings
On the envelop with the photographs is "Keith Wilkinson Ph Orbost 051 510050" and "For Bill Kingsley 4/10/93".
