General Description

When the extinguished agent is discharged, the releasing panel activates the purge panel controller. The controller disables the key operated purge switch, lights the Panel Activated indicator and starts the timing cycle.

The purge fans can NOT be activated until the preset “agent soak time” has expired. When the time cycle is complete, the Purge Ready indicator is activated and the Purge switch is enabled.

Operation of the purge switch will light the Purge Running indicator and activate the remote relay output. This 24vdc output is used to energize a Start Relay (relay by others), located at the purge fan(s).

Simplified Hook-up Diagram


  • Adaptable to most 12-24VDC Control Units.
  • Low standby current consumption.
  • Rugged solid-state construction.
  • Large .8 Inch LCD back-lit digital readout.
  • Precision quartz crystal reference one second incremental countdown.
  • Field programmable for desired delay from 1-99 seconds or 1 second to 99 minutes in 59 seconds.
  • Output to trigger external relay when countdown reaches 0.
  • On-board selectable Sonalert “ticks” in one second intervals and sounds continuously when time reaches zero.
  • On-board LED drivers indicate Power On, Panel Activated, Purge Ready and Purge Running.
  • The Model TA-123PP comes with a key switch controller for Purge Panel applications. When the Purge Running LED is illuminated, a 24VDC output voltage is supplied to activate a remote relay. The remote relay contacts operate the exhaust fans.

Setting the Purge Delay

Switches S1 – S4 are used to set the initial count down time of the TA-123PP. Each is set to the digit of the initial count in the format of MM:SS where MM is the minutes to count and SS is the seconds to count. You may set theminutestocountonS1andS2 (S1is10minandS2is1min) from0to99minutes. S3andS4setthe seconds to count from 0 to 59 seconds. If S1 and S2 are set to 00 minutes, then S3 and S4 may be set from 0 to 99 seconds.

Additional Information

Purge timer is activated by the suppression system discharge contacts. After the preset user-adjustable time delay has expired, the Purge Key Switch is enabled. Operate Key Switch to energize the Purge Fan start relay. Remote relay contacts close to start the Purge Fan.

Specifications: 24 vdc input filtered and regulated 155ma standby, 175ma activated and 335ma purge engaged.