nvent RAYCHEM ACS-30, Руководство по программированию

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Raychem-AR-H58692-ACS30UIT2Programming-EN-1805
3.3. FROST HEAVE MODE
The Frost Heave control mode prompts you to enter the control parameters for your Freezer Frost
Heave Prevention application.
Fig. 3.12 Setup|Frost Heave window
SLAB TEMP SETPOINT:
The slab temp setpoint is the desired maintain temperature for the freezer floor. Based on the
measured control temperature, the ACS-UIT2 will switch the relay output to maintain the system at
the desired setpoint.
Range: 20°F (-7°C)–50°F (10°C)
Default: 40ºF (4°C)
DEADBAND:
If the control temperature is above the setpoint temperature plus deadband, the relay output is
turned off. If the control temperature is below the setpoint temperature, the output is turned on.
Range: 1°F (1°C)–10°F (6°C)
Default: 5ºF (3°C)
FAIL SAFE:
The Fail Safe control button turns the power on or off to the heating cable if the circuit loses all valid
RTDs. When the last remaining sensor for control fails (or communication with the sensor is lost),
the ACS-UIT2:
• Signals an alarm for the failure of the sensor
• Changes control of the circuit to the fail safe control selected
• Changes the control status display to indicate that control of the circuit is in the fail safe state
• Records the events
When the sensor for control is returned to service, the ACS-UIT2 signals the alarm has been cleared,
returns the circuit to its normal control mode, and records both of these events.
Options: Power On or Power Off
Default:
Power On
SCHEDULE:
Tapping on this button will bring up the Scheduler. See Appendix 5.2 24/7 Scheduler on page 127
for more information.