PUFFIN     PAGE 3/2  
     SITE NAME MORWELL - TRARALGON ROAD NR MORWELL - TRARALGON ROAD   SITE NO. 6661  
         
C. CLEARANCE EXTENSION FUNCTION  
     
  GENERAL        
         
  The Flashing Clearance display runs for a minimum time for each pedestrian movement. These minimum times  
  are specified in Special Purpose Timesetting No. 30 for P1 and Special Purpose Timesetting No. 34 for P2.   
  Activation of the CLEARANCE ZONE detectors (i.e. 9 and/or 10 or 11 and/or 12 for P2) provide extension of   
  the Flashing Clearance display up to a maximum time. The maximum times for P1 and P2 are specified in  P1   
  and P2 Clearance 1 Times.      
         
  Between the minimum and maximum times as specified above, the Flashing Clearance display for each   
  pedestrian movement is terminated if the CLEARANCE ZONE detector has been vacated for the period as   
  specified in Special Purpose Timesetting No. 27 (Note: generally set to 1 s).      
             
  ABNORMAL OPERATION          
         
  If the CLEARANCE ZONE detectors (i.e. 9 and/or 10 or 11 and/or 12) do not toggle ON during the Walk and   
  through the Flashing Clearance interval up to the "STANDARD" clearance time, then terminate at this instant.   
  The "STANDARD" clearance time for P1 is specified as the total of Special Purpose Timesetting No. 30 plus   
  Special Purpose Timesetting No. 31, while the "STANDARD" clearance time for P2 is specified as the total of   
  Special Purpose Timesetting No. 34 and Special Purpose Timesetting No. 35.      
     
  Note: When the controller is online to SCATS and a CLEARANCE ZONE detector does not toggle ON   
  for the period as specified by the SCATS TDA message, then a Detector Alarm (DA) will be generated on that 
  CLEARANCE ZONE detector    
 
  If a CLEARANCE ZONE detector does not toggle OFF during the Walk and through the Flashing Clearance  
  interval, then extend to maximum (i.e. the relevant Clearance Time). This may be due to a faulty detector, or    
  a large number of pedestrians.    
       
  Note: When the controller is on line to SCATS and a CLEARANCE ZONE detector does not toggle OFF  
  for the period as specified by the SCATS TDA message, then a Detector Alarm (DA) will be generated on that  
  CLEARANCE ZONE detector. If this occurs then the Flashing Clearance interval will terminate at the   
  "STANDARD" clearance time.    
     
3. OPERATION WITHOUT THE CLEARANCE ZONE DETECTORS BEING              
    USED FOR WALK EXTENSION      
     
  If it is decided that a pedestrian is to operate without the CLEARANCE ZONE detectors extending the  
  walk, either or both of the following 2 methods can be used to allow this to occur.  
 
  P1 Switch detector 13 to the ON position   P2   Switch detector 14 to the ON position  
  Set XSF3 flag     Set XSF5 flag  
 
  In this situation the walk interval will be automatically set to the "STANDARD" walk time (i.e. for P1 the total  
  of Special Purpose Timesetting No. 28 plus Special Purpose Timesetting No. 29 and for P2 the total of Special   
  Purpose Timesetting No. 32 plus Special Purpose Timesetting No. 33).  
 
4. OPERATION WITHOUT THE CLEARANCE ZONE DETECTORS BEING  
    USED FOR CLEARANCE EXTENSION  
 
  If it is decided that the pedestrians is to operate without the CLEARANCE ZONE detectors extending the  
  clearance, either or both of the following 2 methods can be used to allow this to occur.  
 
  P1 Switch detector 15 to the ON position   P2   Switch detector 16 to the ON position  
  Set XSF4 flag     Set XSF6 flag  
 
  In this situation the flashing clearance interval will be automatically set to the "STANDARD" clearance time   
  (i.e. for P1 the total of  Special Purpose Timesetting No. 30 plus Special Purpose Timesetting No. 31 and for P2 
  the total of Special Purpose Timesetting No. 34 and Special Purpose Timesetting No. 35).  
   
DESIGNED BY: SARATH PREMACHANDRA           DATE 23/01/08  
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