Enable

Naztec MIB - This toggle field enables the preempt input for the selected preempt. Set this field to ON to enable the preempt and OFF to disable it. The default value when the controller is cleared and initialized is ON.

Type

Naztec MIB - This field identifies the preempt as a being either a railroad (RAIL) or an emergency vehicle (EMERG) preempt. This setting is included on preempt event log entries. …

Output

Naztec MIB - Each preempt has an output signal that presents the preempts active status. The setting of this field determines during which part of the preempt cycle the output is active. There are three settings as described below.

• TS-2 - The output is active from the time the preempt is recognized until it is complete. The output is not active while the call delay period is timing.
  

• DELAY - The output becomes active when the call is received and includes the call delay period. The output remains active while the preempt is active.
  

• DWELL - The output becomes active when the preempt dwell state is reached. It is not active during the call delay period, begin clearances, or track interval. 

Pattern

Naztec MIB - The Pattern parameter (0-48) allows a coordination pattern to be associated with each preempt during the preempt DWELL interval.

If COORD+PREEMPT is enabled, the controller will run the specified pattern number (0-48) during preempt DWELL.

If COORD+PREEMPT is disabled and a non-zero pattern number is entered in this field, the controller will run free during the DWELL interval, but apply the mode settings (phase recalls) from the split table and any alternate phase or  detector programs called by the pattern during DWELL.

Skip Track if Overide

Naztec MIB - This ON/OFF toggle field allows the track clearance interval to be skipped if the current preempt is overriding a lower priority preempt. Set this entry to ON to cause the track interval not to be serviced. 

CAUTION: Use this feature carefully, it is only appropriate for complex, multi-track clearance situations. Inappropriate use can cause the track clearance interval to be skipped when it should not be.

Coord+Preempt

Naztec MIB - The controller returns to the phases interrupted by the preempt if Coor+Pre is OFF. If Coor+Pre is ON, the controller returns to the phases in the current coordination plan running in the background. This feature is available with all high and low-priority preempts to return to the coordinated phase without the need to transition. Many agencies prefer the Coor+Pre option, especially when coordination is interrupted frequently.