An optional system expansion device.
Allows up to 14 ECU-4, 8, 16 or 8NT SigTEL controllers to be interlinked.
One card required per networked SigTEL controller.
Allows systems of up to 224 lines (14x ECU-16controllers) to be easily set-up.
Any ECU-4,ECU-8 or ECU-16 can take control of the system at any time by the input of a special code