Specifications
  ST900 Family General Handbook 
667/HB/32900/000 Issue 12  Page 20 of 265 
The ST900 Controller uses the reliable and proven Mains Lamp Switch Cards as 
used in the ST800 Controller, offering a total of 32 phases per controller. 
The ST900 Family supports all existing ST800 equipment such as Gemini, Gemini
2
, 
Tele12 OTU, IRM/IMU Card, SDE/SA Card (if the SoundMark Interface is required), 
etc. 
The controller conforms to the UK Highways Agency specification TR2500. 
Figure 1 – ST900 System Overview 










