A facility that prevents the SignallerA person responsible for the operation of the Signalling System, to safely control the passage and regulation of trains, usually located in a Signal Box. from operating an item of signalling
infrastructure. Either a physical item preventing the pulling of a lever or
operation of a button, or an electronic equivalent indicated on the signallers
workstationSee Signalling Workstation.. The formal term for collarA facility that prevents the Signaller from operating an item of signalling infrastructure. Either a physical item preventing the pulling of a lever or operatio... is Reminder ApplianceA device or control used to remind the Signaller that a function such as a button, switch or lever should not be operated/should only be operated under certain ....