Orion System SA E-BUS Controller - Manual (Page 51)

SA E-BUS Controller Technical Guide
Sequence of Operations
51
VAV/Zone Controller Alarms
Failure Mode Alarms
High and Low Supply Temp Alarm
These alarms are activated when the Supply Air Temperature (SAT)
rises above the High Cutoff Temperature Setpoint (immediate) or drops
below the Low Cutoff Temperature Setpoint (for 10 minutes). Both
cutoff setpoints are user-adjustable. This mode shuts off the unit (with
a 3 minute fan off delay) until the mode is cancelled.
This mode is cancelled when the SAT drops 5 degrees below the High
Cutoff Temperature Setpoint or rises 5 degrees above the Low Temp
Cutoff Temperature Setpoint, or when the unit changes back into Oc-
cupied Operation.
High and Low Control Temp Failure
When the Controlling Sensor Temperature rises above the Cooling Mode
Enable Setpoint plus the Control Mode High Alarm Offset setpoint, the
controller will generate a High Control Temp Failure Alarm.
When the Controlling Sensor Temperature drops below the Heating
Mode Enable Setpoint minus the Control Mode Low Alarm Offset set-
point, the controller will generate a Low Control Temp Failure Alarm.
Both offset setpoints are user-adjustable.
Module Alarm
This alarm applies to any E-BUS Module communicating with the SA
E-BUS Controller. The E-BUS modules include the Two Condenser Head
Pressure Module and Water Source Heat Pump Module. If any of these
modules stop communicating with the SA E-BUS Controller or if there is
an alarm on one of these modules, this Module Alarm will be generated.
VAV/Zone Controller Alarms
Space Sensor Failure Alarm
If the controller detects an open or short on the Space Sensor input, this
alarm will be generated.
CFM Sensor Failure Alarm
If the Air Flow Constant (K Factor) is set to any value other than zero,
and the controller does not detect the Airfl ow Sensor, this alarm will
be generated.
Damper Opening Alarm
After initial calibration, if the damper is called to be fully open and
cannot reach that position within approximately 2 minutes, this alarm
will be generated.
Damper Closing Alarm
After initial calibration, if the damper is called to be fully closed and
cannot reach that position within approximately 2 minutes, this alarm
will be generated.
High Space Temp Alarm
If the zone temperature is above the Cooling Setpoint by the Hi Zone
Alarm Offset (user adj.) for the Zone Alarm Delay Period (user adj.),
this alarm will be generated.
Low Space Temp Alarm
If the zone temperature is below the Heating Setpoint by the Lo Zone
Alarm Offset (user adj.) for the Zone Alarm Delay Period (user adj.),
this alarm will be generated.
Damper Feedback Failure Alarm
If the controller fails to detect the actuator feedback signal, this alarm
will be generated.