Point switches or keys

RRI Button Circuit

Indian Railway Signalling Network Rail Railway Signalling Design Specification Method Thales

RRI Button Circuit,Route setting system,Combined Indication & control panel,BUTTON SYMBOLS ON PANEL,Button indications,Route initiation,Route initiation circuits,Time delayTFR, DCR, DZR CIRCUITS,Route initiation circuits,Route initiation destination selected,Route initiation – wrong button pressed,(D)R CIRCUITS,(D)R CIRCUITS,Point switches or keys,EGNR CIRCUIT,Route identification ,Route setting,Signal RLR,(S)PR & (D)PR CIRCUITS

RRI Button Circuit 

points to be operated individually to the required position

After points are set correctly, signal to be cleared

 

Route setting system

With a single action:

points initiated,

points operated,

route checked & locked and

finally signal cleared.

Various route setting systems are in use. NX system is widely used.

 

Combined Indication & control panel

Combined Indication & control panel

 

Each signal is associated with a button.

Main signal is provided with a button colored red.

Subsidiary signal is provided with button colored yellow.

All buttons are spring loaded and they return to normal position

when released after pressing/pulling.

A lamp is incorporated in the base of the button.

BUTTON SYMBOLS ON PANEL

BUTTON SYMBOLS ON PANEL

 

BUTTON SYMBOLS

Button contacts

Button contacts  – M, F, FM,T, TM

Button contacts used for route setting and releasing

Normal – ‘C’ contact made

pressed – ‘F’ & ‘FM’ contact made

pressed and released – ‘F’ contact breaks & ‘FM’ contact made

pulled – ‘FM’ breaks

 

Button contacts

Button indications

First button pressed (at entrance signal) is recognized as entrance button.

Next button pressed (at destination signal) is recognized as exit button.

Entrance button pressed – white light starts flashing.

Exit button is pressed within the specified time – light becomes steady provided route is free.

If the exit button is not pressed within the specified time or the selected route is not free – flashing light ceases.

 

There is no physical interlocking between the buttons like in a Lever Frame.  So a button circuit is provided. Apart from route setting and route releasing functions, button circuit fulfills the following functions –

1.To avoid any conflicting route initiation, only one operation should be possible in a group.

2.To prove that pressing of entrance button is intentional that the exit button to be pressed within 7.5 seconds after the entrance button is released.

3.After entrance button is pressed, transfers the operation to exit button

4.Proves that wrong button is not pressed.

5.Proves that operation is completed and ready for the next operation.

 

Relays in route setting process

Relay Description
(F)R ↓ Energized when button pushed and drops when released. Provided for every button. BR960 Pin Code 212-2x 6F.2B
(FM)R↑ Drops out when button pulled and again energized when button released. Provided for every button. Double wound BR960 Pin Code 060-2x 4F.3B
PBCR↑ Energized when no button pushed in a group. Drops out when any one of the buttons pushed. One for each button ring. BR960 Pin Code 212-2x 6F.2B
PBPR↓

Energized when any button pushed and drops out when released. One for each push button ring. BR960 Pin Code 212-2x 6F.2B

TFR ↓ Transfer relay. Transfers the button operation from entrance to exit. Energized after entrance button pushed and released. Drops out with either exit button pushed within specified time or after a time delay. One for each button ring. BR931 Pin Code 023-12F.4B

 

Relay Description
(F)R ↓ Energized when button pushed and drops when released. Provided for every button. BR960 Pin Code 212-2x 6F.2B
(FM)R↑ Drops out when button pulled and again energized when button released. Provided for every button.

Double wound BR960 Pin Code 060-2x 4F.3B

PBCR↑ Energized when no button pushed in a group. Drops out when any one of the buttons pushed. One for each button ring.             BR960 Pin Code 212-2x 6F.2B
PBPR↓ Energized when any button pushed and drops out when released. One for each push button ring.  BR960 Pin Code 212-2x 6F.2B
TFR ↓ Transfer relay. Transfers the button operation from entrance to exit. Energized after entrance button pushed and released. Drops out with either exit button pushed within specified time or after a time delay. One for each button ring. BR931 Pin Code 023-12F.4B

 

Relay Description
DJR ↑ Clear time delay relay. Slow release with two capacitor slugs. Drops away one second after DCR drops, or 7.5 seconds after TFR picks. Drops away one second after DCR drops. One for each push button ring. BR934A Pin Code 063-8F.4B with H/O(D) 470 µF 330W & H/O(S) 3300µF 330 W .
Route NLR ↑

(Latched)

Normal (route) lock relay. Magnetically latched relay is up when the route is normal. To call a route this relay unlatches. Once unlatched, the NLR cannot re-operate until the signal is On and FOAL. One for each route. BR935 Pin Code 011-11F.4B
Route RLR↓ Reverse (route) lock relay. Ordinary acting neutral relay. Contains all the route controls. One for each route. BR931 Pin Code 023-12F.4B
NR↓ Normalizing relay. Energizes when route entrance button pulled or with TORR. One for each entrance button.
DZR↓ Destination invalid relay. Energizes when a wrong button is pressed. One for each push button ring. Energizes when route entrance button pulled or with TORR. One for each entrance button.

 

Route initiation –entrance selected

Route initiation

 

Route initiation circuits

Route initiation circuits

Route initiation circuits

Route initiation circuits 2

Time delayTFR, DCR, DZR CIRCUITS

TFR energizes after entrance button pushed and released.

DCR re-picks up after exit button released to indicate that operation is completed.

DZR picks up when wrong button pressed.

 

Time delayTFR, DCR, DZR CIRCUITS

 

Route initiation circuits

DJR drops away 7.5 seconds after TFR picks or one second after DCR drops.

DJR↓  releases (S)R & (D)R. Then (S)PR & (D)PR releases.

DJR hold switch in relay room is to hold  (S)R & (D)R for longer time for Testing.

Route initiation circuits 5

Route initiation destination selected

 

 

Route initiation destination selected

Route initiation – wrong button pressed

Route initiation - wrong button pressed

(D)R CIRCUITS

(D)R CIRCUITS

EGNR CIRCUIT

Auto Signals with  replacement facility, controlled from two locations.  F2R is same as (F)R

Double wound BR960 Pin Code 060-2x 4F.3B

 

EGNR CIRCUIT

 

Point switches or keys

Points are operated either by route initiation or by Individual point switches/keys.

Each switch/key is having three positions N, R and C.

During route setting process switch/key is kept in C (CR contact made)  position

 

Switch/Key operated to ‘N’ (NR contact made)- operates the point to Normal.

Point completes operation to ‘N’ even if it is brought  back to ‘C’ position subsequently.

Switch/key operated to ‘R (RR contact made) – operates the point to Reverse.

 

Point completes operation to ‘R’ even if it is brought  back to ‘C’ position subsequently.

Corresponding point indications are provided at point switch/key.

Individual signal operation is still possible if the points are available  in the required position, even if the switch/key is not in it’s ‘C’ position.

 

Point switches or keys

 

Route identification

When a signal is having more than one route – route on the extreme left as seen facing the signal 43 is identified  as ‘43A’. Next extreme left route will be ‘43B’

Where the route is having more than one class of route the class of route is identified by bracketed suffix.  e.g. 43A route is having main class, warning class, call-on, and shunt.

  43A(M) – main class-full O/L available.

   43A(W) – warning class – full O/L available.

   43A(C)  – Call-on class – berthing track occupied.

   43A(S) –  Shunt class used for shunting with PLGS.

 

Route setting

Route setting

Route setting

Signal RLR

Energised when-

Points are initiated to set to the required position if not already set.

Points will move to the called position

After points are set to correct position and locked the detection relays NWKR/RWKR will pick up.

 

(S)PR & (D)PR CIRCUITS

(S)PR & (D)PR CIRCUITS

 

 

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