User manual

Service Menu Parameters
Liebert
®
iCOM
®
134
8.2 Service—Standby Settings / Lead Lag Menu Screen
Standby Settings / Lead Lag allows the user program lead-lag setup when units are connected in a
Liebert iCOM U2U network.
Figure 113 Standby settings / lead-lag screen
S502 Number of Standby Units—Selects the number of units that will be in Standby mode. When
a unit is in standby mode, the fan will be Off and no cooling will be provided.
S503 Rotation Frequency—Controls when a rotation will occur between the standby units and the
operating units within a network.
S504 Rotate at—Sets the hour and minute of the rotation.
S505 Rotate by—Determines the number of positions to rotate by. Example: If there are six units in
a unit-to-unit network and units 1, 3 and 5 are in standby and this parameter is set to “1,” then at the
next rotation units 2, 4 and 6 will be placed in standby and units 1, 3 and 5 will become operational.
S506 Stdby Fan Timer at Reheat/Hum—Sets the time that the fan will operate after a unit enters
standby or sleep if the reheat or humidifier was operating when commanded to turn Off. Default is 30
minutes; range is 3 to 360 minutes.
S507 Perform one Rotation—Setting this parameter to YES will perform one rotation without
waiting on the rotation timer to expire.
S508 Cascade Units—Allows units to activate in Standby mode if the room temperature cannot be
maintained by the non-standby units. If “Yes” is selected, the cascaded units can perform all functions
when activated from standby. This parameter can also be set for Cooling Only or Cool / Heat / Fan
(available in TW3 only).
S509 Cascaded Units Delay—Sets the delay time to stage on each unit as they are staged on during
increased demand. When the first unit is started and the cooling request is high enough to start the
timer is started and once the timer has expired the next unit will start. This parameter range is 0-30
minutes. The factory default is 5 minutes.
S510 Cascaded Units Quick Start—Sets a delay to the staging on each unit after a power cycle of
the master unit. This is used to get the units to start faster after a power cycle and use this parameter
instead of S509. When the master unit is started and the cooling request is high enough to start the
timer is started and once the timer has expired next unit will start. The control will not revert back to
S509 until all required units have been restarted in cascade. This parameter range is 0-30 minutes.
The factory default is 2 minutes.