Route Set Flashcards
Are the following relays located in the relay room or cupboard location.
HR-HDR-DR-UCR-VNR-VCSR-RUR-NWKR-WZR-ALSR-NWR
Location - HR HDR DR VNR,
Relay room
What is the purpose of the NLKPR/RLKPR
They are the lock and detector repeat relays. Prove points are locked and detected in the correct position and locked by the interlocking (RUR up, NLR down so WZR is down) before a signal can clear
What is the purpose of a track circuit
To prove the signal and trainstop have returned to stop after the passage of a train.
Why are magnetically latched relays used
They provide memory storage functions so that if power is lost, it will remain in the same position.
Used in points NLR/RLR circuits and signal route NLR/RLR circuits
What is the purpose of the WZR
Indicates if the points are free and would respond to a call. slow to release relay to prevent RUR from dropping out during the operation of point lock relays.
What is the purpose of the USR
Holds locking of a route after train enters the route
What is the purpose of the UCR
Checks all trakc snad points detection for signal controls
What is the purpose of the ALSR
Hold locking if signal placed normal in face of train
What is the purpose of the NKR and the difference to a NWKR
Indications points Normal/reverse. Local to points.
NWKR/RWKR indicates points Normal/Reverse at the interlocking
What is the purpose of EMR
What is the purpose of the CeR
defines and initiates route to be set
What is the purpose of the MUR
To ensure that the next button operated initiates the finish operation for the route
What is the purpose of a guards indicator and what colour is it
To indicate to a train guard that the signal ahead has cleared and they can depart when safe.
What is the purpose of the MUKR
it is a repeat of the MUR, gives flashing red or green indications. Indicates to the signalman if the machine is in use or finish.
What is the purpose of the (FM)R
emergency replacement of a signal after the route has been set
what is the purpose of the finish timing relays FnJR and FnJPR.
provide the timing sequence initiated by the finish function to provide non storage feature of the system.
routes cannot be pre-selected until a train has exited the route.
What does the NLR prove
the signal has returned to stop
the signal is not approach locked
the route RUR is de-energised and therefore not capable of setting points or clearing the controlling signal
What is the purpose of the RUR and what does it prove
It proves the NLR is latched down. it is used to set points and clear the entering signal, also checks for any conflicting routes are normal before they route can be set.
What is the purpose of a lock relay
they perform route and interlocking functions. One relay has to be driven and proved fup/down before the other can be driven down/up.
What is a latched relay and what is the purpose
It is a relay that is magnetically latched and has a memory storage function remaining in the last operated position.
Whats the purpose of the WJR
To prevent the points being called if there is bobbing of track circuits.
What are NOLR ROLR and what are their purpose
Over lap relays. Providing setting of points to an alternative route should the overlap be clear and the points free to move.
What is a lock out
when both lock relays are down at the same time, meaning the WZR is also down.
