Signal Relay
Maker and role
The Siemens and General Electric Railway Signal Company Limited, Manufacturer
See full details
Object detail
Accession number
2011.222
Description
A glass cube with a metallic lid holding 4 coils and sixteen connection points. There are glass windows on all four sides and a paper tag.
Marks
SGC / MADE IN ENGLAND Maker's Mark
Media/Materials
Credit Line
The Siemens and General Electric Railway Signal Company Limited. Signal Relay, 2011.222. The Museum of Transport and Technology (MOTAT).
Public comments
Kia ora Ken, thank you for your comment. I will follow up in an email.
- MOTAT Curatorial Research posted one year ago.
This is a vital signalling relay used to control level crossing alarms. It consists of two 4 Ohm track circuit relays in one housing but the two relays are mechanically interlocked so that a train approaching the crossing will completely de-energise one track relay to start the alarms. As the passes over the crossing and drops the second track relay, the mechanical interlocking will only let the second relay partially drop thus not activating the alarms. When the rear of the train clears the approach, the first track picks and the alarms cancel. The rear of the train clearing the other track let the interlock restore and the system returned to normal. This particular relay is a NZR signals catalogue number SR723. As far as I know the last one in the North Island was removed from Mangapehi in 1986 and the last one in the South was removed from Papanui around 1991.
- Ken Ashman posted one year ago.