Emerson iCOM user manual Autorestart, Loss of Power Alarm, Fan Alarm / Fan Protection Settings

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Operation

Autorestart

When there is a loss of power to the cooling unit and power comes back, the unit will return to its pre- vious operating status—on if it was on before the power off, off if it was off.

When power returns, the autorestart time—time-selectable: Single Unit Auto Restart (Service Menu, Options Setup)—controls the start of the unit. The autorestart time runs in a loop, starting the next unit each time when elapsed, starting with Unit # 1.

Loss of Power Alarm

A Loss of Power Alarm is activated when power is restored after an interruption. If acknowledged, the alarm resets automatically after 30 minutes. This alarm can be set to different event types (Message, Alarm or Warning) and can be disabled under menu item Loss of Power (Service Menu, Set Alarms).

NOTE

Loss of power alarm will be activated only on units that had the fan on before power was lost.

Fan Alarm / Fan Protection Settings

The fan operation is protected by two digital devices: motor protection (optional) and a differential pressure switch. The motor protection monitors for main fan overload and the differential pressure switch ensures that the blower(s) are moving air. If either protection device triggers, an alarm will be announced by a buzzer, alarm relay and event to monitoring after an adjustable time-delay (Main Fan Overload and Loss Of Airflow in Service Menu, Set Alarms).

The time delay at the unit start is always five seconds shorter than the control delay (to avoid short component starting when the fan is not working). During operation, the fan delay is fixed to

15 seconds.

There are two selection possibilities for both, Loss Of Airflow and Main Fan Overload:

•Shutdown—stops the unit (intended for DX models).

•Disable—stops the humidifier, electrical heaters and dehumidification; allows cooling and free-cooling only (intended for chilled water models / external cooling).

NOTE

When the Main Fan Overload alarm is active, the Loss of Airflow alarm is masked out.

3.1.2Chilled Water Units with Variable Speed Motor

VSD Fan Speed (Auto or Manual VSD Fan Speed Control)

The parameter VSD Fan Speed (Service Menu, Setpoints) allows the cooling unit's fan motor speed to be set for:

•Auto operation: when set to Auto, the speed of the VSD (variable speed drive) motor follows the position of the chilled water valve based on predetermined logic for cooling and dehumidification operation.

•Manual operation: when set to Manual, the speed of the VSD motor follows user input as set either locally at the cooling unit's Liebert iCOM display (under VSD Setpoint in Service Menu, Setpoints) or remotely using Modbus BMS signal with an optional Liebert IntelliSlot® 485 card.

VSD Setpoint (VSD Fan Speed Setting)

If the VSD Fan Speed Control (Service Menu, Setpoints) is set for Manual, the VSD Fan Speed Set- point (Service Menu, Setpoints) may be set for the desired speed of the variable speed motor.

Depending on the product control design, there may be an internal minimum speed, as defined by that specific product operation, while the customer input may be set for 0-100%:

•Fan speed may be set locally at the unit using the Liebert iCOM display.

•Fan speed may be set remotely via a BMS signal (sent via Modbus using an optional Liebert Intel- liSlot 485 card), which then transmits to the unit local control.

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Contents Liebert iCOM Page Table of Contents Teamwork Installing a Liebert Icom UNIT-TO-UNITNETWORKMounting a Large Display on a Wall Figures Tables Large and Small Displays FeaturesESC Icon Key Name Function Keyboard icons and functionsStatus menu, large display, graphical view Navigating Through the Liebert iCOM Menus Accessing SubmenusAccessing Submenus on Small Displays Accessing Submenus on Large DisplaysMenu tree-Small display, stand-alone or networked Entering a PasswordStatus Menu System View Status Menu Unit 1 View User Menu Service Menu UnitAdvanced Menu Unit Viewing Multiple Units with a Networked Large Display Service Menu Unit #Advanced Menu Unit # SET User menu icons Service menu icons Unit/Fan Control Start Stop Single Unit FunctionsAutorestart Loss of Power AlarmFan Alarm / Fan Protection Settings VSD Setpoint VSD Fan Speed SettingPump Down High Pressure AlarmCompressor Timing-Units With Two Compressors Digital Scroll High TemperatureCompressor Sequencing Motorized Ball Valve in Digital Scroll Units Service Offset-Changing System Pressure SettingsMBV Operation After Compressor is Turned Off Temperature proportional band Temperature Proportional BandTwo Single-Step Compressors Without Unloaders-Two-Step Compressor ControlCompressor Proportional Bands One Single-Step Compressor Without Unloaders-One-StepTwo compressors with unloaders four-step Two Compressors With Unloaders-Four-StepDigital scroll capacity modulation, 10-100% variable Digital Scroll CompressorsChilled Water Control Temperature Control-Second Cooling SourceDifferential Temperatures / Controls Comparator Circuit Delta T Temperature Difference Between Room and GlycolSecond cooling source and compressorized cooling Dual Cooling Source Temperature Control-ReheatReheat configuration types Glycool Cooling-Free-CoolingHeat On ½ Dead Band 100% Off ½ Proportional Band Decreasing TemperatureSCR Reheat Tight ModeStandard Mode Humidification Dehumidification Humidity ControlHumidification Parameters for infrared humidifier control Humidification Infrared HumidifierExternal Humidifier Control-Optional Dehumidification Compressor Quantity Dehumidification With Comp settingsDehumidification Dehumidification Low LimitControl Types Temperature and Humidity Control TypesReheat During Dehumidification Humidity Sensor Reading Control Types Supply Limit-Optional High and Low, Temperature and Humidity EventsCustomer inputs User Inputs / Customer InputsEvent Types Time DelayEnable or Disable Event Types and PropertiesMain FAN Overload Event notifications-large or small display Possible Event NotificationsCalculation of Next Maintenance and Diagnostics Next Maintenance CalculationCalculating Unit Wellness Compressor 1 / 2 Settings and Diagnostics Parameters for Next Maintenance CalculationGeneral Maintenance Settings Fans / Heaters / Humidifier Settings and DiagnosticsNo Teamwork Teamwork ModeTeamwork Modes Application of Teamwork ModesTeamwork Mode 1 with two cooling units Standby and Cascade Standby Rotation Typical Standby Lead/Lag FunctionU2U Hardware Cables and Network Switch Placement of Cooling UnitsMinimum Network Switch Requirements Sample Liebert iCOM network configurations Wiring for Unit-to-Unit Communications-U2ULiebert iCOM U2U Ethernet Network Combining Large and Small Displays on a U2U Network Wiring a Liebert iCOM U2U Network Small DisplaysLarge Displays Wall-Mount Large DisplayWiring a small display for stand-alone operation Wiring a large display for stand-alone operation Liebert vNSA Ports available for connecting Liebert iCOM control devices298 84mm 305mm 14.25 362mm DPN001136 Rev Necessary Mounting Items Location ConsiderationsMounting Instructions Liebert iCOM display dimensions Event log parameters Spare Part List-Large Display OnlySetpoints parameters Spare part list parameters-large display onlySensor data Set alarms parametersActive alarms parameters Active AlarmsDisplay setup parameters Total run hours parameters Timer parameters-Sleep ModeService contacts parameters Service Menu Parameters Unit diary parameters Unit Diary-Large Display OnlyMaintenance / wellness settings parameters Standby settings / lead-lag parametersWellness COMP2 Wellness HEAT2 Diagnostics / service mode parameters ALM REL 7of Delay Enable Disab Enable Disab Comp 1 Overload Unit X Disconnected WRN Loss of Power LOP MSG, WRN, ALM Call Service MSG, WRN, ALM High Temperature Sensor calibration / setup parameters System / network setup parameters-large display only GBP Network setup parametersStatic RAM Not Available, Invalid, OK HUM Steam Options setup parametersService contact info parameters Service Menu Parameters Service Menu Parameters Page That Ne tIti Ti n
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