Section 4: Glossary of Control Functions
Humidity Alarms
Humidity alarms are caused when the humidity detected by the remote sensor in Zone 1 exceeds the programmed High or Low trip-point. Trip- points are selected in 1% RH increments from the display. Entering 00 disables an alarm. A Humidity Alarm activates the Common Alarm output.
High Range—up to 80% RH.
Low Range—down to 20% RH.
Humidity Lockout
A Form C contact labeled Humidity Lockout is energized when a humidity reading exceeds a lockout trip-point. The relay is de-energized when humidity drops to 2% RH below the High Humidity Trip-point, or when humidity rises to 2% RH above the Low Humidity Trip-point. To use this contact for a single control function (increase or decrease humidity) disable one of the Humidity Alarms.
Inactive Unit
An inactive unit is one that is not programmed to the RAC2-8 system. This appears in an error message if you try to Override a unit that the system does not recognize.
Interval
The Interval is the time period (in days) used to program the Autosequencing and Standby Testing functions. The interval is user selected from the display. Range—0 to 99 days.
Labels
Each unit may be labeled with a 2 digit number from 01 to 99. If you prefer something other than 01 through 08, unit labels can be selected from the display.
Manual Override
A switch located inside the RAC2-8 enclosure turns all units ON. This action also annunciates an alarm, energizes the Common Alarm output relay, and energizes the Control Lockout relay. To return to normal operation, turn this switch off and clear the alarm. Refer to Override for manual operations from the display.
Modem
The RAC2-8 includes an EIA-232 modem port to provide remote display of alarms. This same port also allows system monitoring and programming from a remotely located terminal. Operation from a remote terminal requires a Password after the “LOG ON: ” prompt. If a remote terminal is active, alarms are displayed at the terminal instead of being dialed out. The modem selections such as phone number, redial interval, etc., are made from a local or remote terminal. Modem baud rate is selected using switches inside the RAC2-8 enclosure.
