3 Stage Electric Reheat – With Dead Band - Emerson Liebert iCOM Training And Service Manual

iCOM
Control Training and Service Manual
3 Stage Electric Reheat – With Dead Band
In the above example that the control band begins at the 70°F temperature set
point plus ½ of the programmed temperature proportional band value.
As the return air temperature decreases Reheat 1 is activated at 68.2°F or ½ of
the dead band value plus 33% of the heating control band. If the return air
temperature continues to decrease Reheat 2 will activate at 66.9°F or ½ of the
dead band value plus 66% of the heating control band. If the return air
temperature continues to decrease Reheat 3 will activate at 65.6°F or ½ of the
dead band value plus 100% of the heating control band.
When the return air temperature starts to increase, Reheat 3 is deactivated at
66.9°F or ½ of the dead band value plus 66% of the heating control band. Reheat
2 is deactivated at 68.2°F or ½ of the dead band value plus 33% of the heating
control band. Reheat 1 is deactivated at 69.5°F or ½ of the dead band value plus
0% of the heating control band.
Remember the temperature dead band value is used by the control to shift
the cooling on/off operations away from the temperature set point.
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