Emerson Liebert iCOM, Manual

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Service Menu Parameters
107 Liebert
®
iCOM
®
for Liebert DSE
™
compressors can only be set to Return or Remote control type l. This parameter can only be changed
in the service menu. The range is Supply, Return or Remote Sensor. The default setting is Return.
S103 Temperature Setpoint Act/Set —Selects a return temperature that the cooling unit will
maintain by applying cooling and or reheats. This is adjustable from 41-104°F (5-40°C). The default is
73°F (22.7°C).
There are two values in this field. The Temp Set value is the temperature that has been set by the
user to control the temp. The Temp Act value is a read only value that indicates if another routine,
like supply compensation has internally modified the Temp controlling value. If compensation has not
been activated, then the ACT and SET will always match. This parameter is adjustable from
41-104°F (5-40°C). The default set value for Supply is 64°F. The default set value for Return and
Remote is 73°F.
S104 Temperature Control Type —Sets the type of control to be followed Proportional, PI or
Intelligent.
S106 Temperature Proportional /Integral —Adjusts the activation points of compressors or rate
of change based on the actual sensor values deviation from setpoint. The smaller this number the
faster the compressors and valve(s) will increase capacity. Too small of a number may cause the unit
to short cycle the compressors or excessively reposition the valve.
S107 Temperature Integration Time —Adjusts the capacity of the unit based on time away from
setpoint so that accurate temperature control can be maintained. The proportional and integral work
together to maintain setpoint. Large P-Band with Small I-Time is typical when controlling to supply
air.
S108 AutoSet Enable —Sets the temperature and humidity proportional bands automatically based
on the type of unit when this parameter is set to “YES” and if teamwork modes are selected. To
change the proportional bands, this parameter must be set to “NO”. If supply or remote sensors are
used, then this value is always set to “No.”
S109 Temperature Deadband —Avoids overshooting of the setpoint and cycling between the
reheats and cooling. The value entered in this field will be split in half by the temperature setpoint.
Example: If the temperature setpoint is 70°F (21.1°C) and a 4°F (2.2°C) deadband is set, then no
cooling will be activated until 72°F (22.2°C) and no heating will be activated until 68°F (20°C) is
reached.
S110 Supply Limit Enabled/Setpoint —Chilled water units may be set up with the supply air
sensor to maintain a minimum air temperature under a raised floor to help prevent condensation. In
order to avoid supply temperatures that are too low, the Supply Limit can influence the opening of
three-point or analog actuators or the output of analog valves. The control compares the deviation
from the return air setpoint and the supply limit setpoint, and calculates the output to the actuator
from the smaller deviation.
S111 Heater Deadband —Changes the amount of deviation below the temperature setpoint that the
heaters will cycle On and Off on Liebert HPM ™ units. This value is added to the heating side of the
normal temperature deadband.