CONTROLLERS
The temperature control system is comprised of a single channel, dual output controller. On/off
outputs are used to drive heaters and cooling solenoids. An additional controller is used to control
the humidity (if that option is ordered). Both controllers are configured and tested at the factory to
ensure proper performance.
Controller operating procedures and factory default settings are listed in the Appendix. Default is
temperature display in ºC. For ºF, consult factory for details. In addition, see the separate
controller manual for more details on controller operation, menus and available settings.
Due to individual circumstances, it maybe beneficial to modify the default settings to best suit an
applications. Examples include alarm and communication settings.
NOTE:
On power up, the temperature and humidity controllers allow the system one minute to
stabilize prior to turning on outputs. Therefore it is normal for the unit not to turn on heating or
cooling, or humidify for a full minute on power up regardless of set-points and cabinet conditions.
TEMPERATURE DEVIATION ALARM
All units are equipped with an alarm system that constantly monitors temperature to ensure the
user is notified if the cabinet goes into an alarm condition. Notification occurs via a RED indicator
LED and an audible alarm. Temperature alarms will occur once the alarm condition has been
present for 15 minutes. This delay is in place to avoid nuisance alarms associated with door
openings.
Example of Deviation value:
Set point = 30
°
C
Alarm high = 5
°
C
Alarm low = 3
°
C
∴
High Alarm = 35
°
C and Low Alarm = 27
°
C
NOTE:
When powering up the chamber, if the actual interior chamber temperature varies from
the setpoint, immediately set the deviation amount to a large enough margin in order to allow the
chamber to reach the temperature setpoint. If the deviation amount is too small the alarm will
sound until the chamber is within the min / max deviation range. The temperature deviation alarm
is preset to 50°C above or below set point.
