Sequences Of Operation - LG AR-DR11-08A Installation And Operation Manual

Sequences of Operation

Sequence of operation varies based on unit configuration. See submittal documentation for configuration detail. Custom applications may have
sequences that vary from those described below.
Unit Availability
Unit Start Command. The unit is available for operation when the following conditions are met:
• After powering up and a five-second initial delay.
• There are no active shutdown alarms.
Unit Commands
Occupied Start: The unit operates in the occupied mode under any of the following conditions, based on user selection:
• BMS command
• Digital hardwired input
• Daily schedule
Occupied Auto Mode: In occupied auto mode, if space reset is enabled, the unit cycles on and off based on space temperature. The unit
starts when the space temperature exceeds the set-point plus a deadband. The unit transitions to off/standby when the set-point is achieved.
Occupancy Timed Override Input: A user can override the unit, placing it into occupied mode by pressing the occupancy override button. The
unit then remains occupied for the occupancy override duration.
Unoccupied Start: The unit operates in the unoccupied mode under any of the following conditions:
• Unoccupied heating
• Unoccupied cooling
• Unoccupied humidification
System On
System on mode occurs when there is an active occupied or unoccupied start command. When a start command becomes active the follow-
ing steps occur:
• Actuators are powered.
• Fan damper delay timers start counting down from their initial value.
• Individual fan delays start counting down from their initial value.
• Fans are commanded on after timers have expired, and damper end switches prove dampers are open.
• The startup delay timer starts counting down from its initial value.
• After the startup delay timer expires, thermodynamic sequences are allowed.
Power Loss Auto Restart: If power loss auto restart is enabled, the unit returns to the last known operation state based on the unit enable
value after an application restart or power loss. If power loss auto restart is disabled, the unit remains off until commanded on.
Shutdown Alarm Auto Restart: If the shutdown alarm auto restart is enabled, the unit remains enabled while a shutdown alarm is active,
allowing the unit to automatically restart after a shutdown alarm is cleared. If the shutdown alarm auto restart is disabled, the unit is disabled
when there is an active shutdown alarm. This requires the unit to be re-enabled manually after the shutdown alarm condition is cleared.
Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. "LG" is a registered trademark of LG Corp.
• The unit has been enabled at the Unit Enable screen or by the
building management system (BMS), and the unit service switch, if
installed, is in the on position.
• Always occupied
• Always unoccupied
• Unoccupied dehumidification
• Unoccupied multi-zone heating
• Unoccupied multi-zone cooling
CONTROLLER
Sequences of Operation
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