Vertiv SmartRow DCR, Инструкция по установке и эксплуатации

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6.4.1 Prevent High-temperature Threshold from Starting All Liebert PDX/PCWs
The high-temperature threshold, when enabled, will prompt the Liebert iCOM to start all cooling units.
The function is intended to prevent high temperatures in the SmartRow DCR. However, when the second
Liebert PDX/PCW is activated by this parameter, the cooling unit will remain On until you manually
acknowledge it’s activation by pressing the horn button on the Liebert iCOM or over remote monitoring.
To prevent the high-temperature threshold from starting the second Liebert PDX/PCW, go to the Service
Menu > Standby Lead-Lag > S513: Start all Standby units by HT. Change the setting to “NO.”
NOTE: While this setting is disabled, the combination of Teamwork Mode and Cascade settings will
achieve the same result (see
Additional Settings for 20-kW, 3- to 6-rack Systems—N+1 cooling Only
(2 PDX/PCWs - one cooling unit on, one in standby) on the previous page). During thermal overload
scenarios the redundant Liebert PDX/PCW will be activated to provide supplemental cooling and
automatically reset when no longer needed.
NOTE: The default high temperature threshold is 80°F. The user may reset this threshold once the
temperature drops 4°F below the setpoint. This threshold operates only off the return air temperature
sensor.
6.4.2 Prevent False High-humidity Alarms
Delaying the humidity alarm will prevent false high-humidity alarms during a rotation of cooling units. The
humidity sensor in the standby Liebert PDX/PCW will report a false high humidity reading because it is
briefly not in an active air stream.
To delay the alarm, make this setting change in
Service Menu > Set Alarms (Page 4) > S241 High humidity: 120 second
The default delay is 30 seconds. The maximum is 9,999 seconds.
6.5 Additional Settings for 36-kW, 5- to 10-rack Systems—N Cooling Only
(2 PDX/PCWs - both units on)
These settings apply to a SmartRow DCR that has two Liebert PDX/PCWs operating at a time. The
system’s cooling capacity is 36 kW.
Before making these changes, complete the adjustments in Liebert iCOM Setup for all SmartRow DCR
Types on page 55.
6.5.1 Ensure Even Airflow to all Racks During Low Heat Load
The compressor in the secondary Liebert PDX/PCW may shut off if the heat load is low. The intent of the
setting is to avoid over-cooling and undesired dehumidification. This change rotates the designation of
“primary cooling unit” between the cooling units to help balance compressor run hours. If the fan in the
secondary PDX/PCW unit were to shut-off, some racks would experience hot spots. These settings also
ensure that the temperature readings from all racks are factored into the cooling capacity calculation
Vertiv | SmartRow DCR Installer/User Guide | 59