Liebert iCOM Microprocessor TM-10098 - Manual (Page 32)

iCOM
Control Training and Service Manual
Note: in the above example that the control band begins at the 50% humidity set
point and has a length of 4%, which is ½ of the programmed humidity proportional
band value.
As the return air humidity increases, dehumidification operation is activated at
54%RH or 100% of the dehumidification control band. When the return air
humidity starts to decrease, dehumidification operation is deactivated at 52%RH or
50% of the humidity proportional control band.
1 Stage Compressorized Dehumidification – With Dead Band
Humid Set Point: 50%
Proportional Band: 8%
Dead Band: 2%
50 51 52 53 54 55
Increasing Humidity
Dehumidification On
Dehumidification Off
Humidity Set Point - (1/2 Dead Band +1/2 Proportional Band)
DB
Note: in the above example that the control band begins at the 50% humidity set
point and has a length of 5%, which is ½ of the programmed dead band value plus
½ of the programmed proportional band value.
As the return air humidity increases, dehumidification operation is activated at 55%
RH or ½ of the dead band value plus 100% of the dehumidification control band.
When the return air humidity starts to decrease, dehumidification operation is
deactivated at 53%RH or ½ of the dead band value plus 50% of the humidity
proportional control band.
2-Stage Dehumidification, Compressorized Direct Expansion (DX)
Systems
The basic dehumidification control band is established at the humidity set point
with the length equal to ½ of the programmed humidity proportional band value.
When 2 stage dehumidification is selected, the controller works as follows.
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