Setting up the sash switch - Triatek - LIT-12014409 - HMS1655 Fume Hood Controller

The HMS1655 uses digital input 1 (DI-1) as the sash switch input. This capability enables the HMS1655 to monitor the sash of the fume hood and use its status to delay the sounds of alarms and hold the analog output fixed until the sash returns to the closed position. The Sash Switch option on the Controller Setup menus enables configuration of the sash switch input as required by the specific application.

After you select the contact type associated with the sash switch, either N.O. or N.C., set the delay as required by the specific installation. This delay in minutes specifies the period in which the sash alarms are muted and the occupancy mode remains active. The minimum period of this delay is one minute, and can be as long as four hours in one-minute increments. When the sash is opened and activates the sash switch, the operation mode automatically switches to Occupied if not already in that mode. The sash delay timer initiates and inhibits the audible sash alarm. The HMS1655 can activate an automatic sash closer when the sash delay timer expires. To use this feature, configure the relay output 1 (RL-1) for Timer-Based mode. See Setting up the alarm relay for more information.