Emerson Liebert iCOM Training And Service Manual page 60

If the end user enables the parameter "Start all Standby units by HT" all available
standby units will turn ON and will continue to run until the return air temperature
in the unit in alarm decrease to approximately 5°F below the high temperature
alarm setpoint.
Example A: In a basic 4 unit configuration, units 1, 2 and 3 are programmed to be
operating and unit 4 is programmed to be standby. The "Rotate By" parameter is
programmed to 1 unit. When the control calls for the units to rotate by "1 unit" the
following sequence occurs:
Unit
Initial Setup
Number
1 Operating
2 Operating
3 Operating
4 Standby
In this configuration, by the fourth rotation the units are back to the original setup -
units 1, 2 and 3 operating with unit 4 in standby.
Example B: In a basic 4 unit configuration, units 1 and 2 are programmed to be
operating and units 3 and 4 are programmed to be standby. The "Rotate By"
parameter is programmed to 2 units. When the control calls for the units to rotate
by "2 units" the following sequence occurs:
Unit
Initial Setup
Number
1 Operating
2 Operating
3 Standby
4 Standby
In this configuration, by every second rotation the units are back to the original
setup - units 1 and 2 operating with units 3 and 4 in standby.
iCOM
Control Training and Service Manual
st nd
1 2
Rotation Rotation
Standby Operating
Operating Standby
Operating Operating
Operating Operating
st nd
1 2
Rotation Rotation
Standby Operating
Standby Operating
Operating Standby
Operating Standby
59
rd th
3 4
Rotation Rotation
Operating Operating
Operating Operating
Standby Operating
Operating Standby
rd th
3 4
Rotation Rotation
Standby Operating
Standby Operating
Operating Standby
Operating Standby