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SK2018 PCG(H)-V/P-AECM-001
F.5.
Control Logic Specification
F.5.1.
Unit Power ON/OFF
a)
The unit is turned ON when any of the fan speed inputs (G2/G1/G0) are ON, or modulating signal input is more
than 2 VDC.
b)
The unit is turned OFF only if all of the fan speed inputs (G2/G1/G0) are OFF and modulating signal input is less
than 2.0 VDC.
F.5.2.
Alarm Protection and Error Display
a)
If the float switch is open for 5 minutes or EC motor fails, then the (NC) voltage-free alarm contact shall be open
and the (NO) voltage free alarm contact shall be closed.
b)
If the float switch is open for 10 minutes or EC motor fails, the LED display reports a condensate management
failure (see table on the next page).
F.5.3.
Drain-Pump Operation
a)
When the unit turns ON:
i.
If Ti1 < 57.2ºF, the drain pump turns ON.
ii.
If 57.2ºF<=Ti<60.8C, the drain pan keeps original state.
iii.
If Ti1 ≥ 60.8 ºC, the drain pump turns OFF.
b)
When the unit turns OFF and the drain pump is ON:
i.
The drain pump will remain ON for 5 minutes and then turn OFF.
c)
At any time:
i.
If the float switch is OPEN, the drain pump will turn ON.
ii.
If the float switch is OPEN and then CLOSES, the drain pump will remain ON for 5 minutes, and then
turn OFF.
F.5.4.
Swing and Louver Control
a)
When the unit is OFF, the louvers are closed (angle at 100º against vertical).
b)
When the unit turns ON, the louvers open (angle at 87º against the horizontal).
c)
When the unit turns OFF, the louvers return to a closed position (100º against the vertical).
F.5.5.
Modulating Signal Input
a)
The standard configuration is for 0~5VDC modulating signal input.
b)
The optional configuration is for 0~10VDC modulating signal. To set the PCB to the optional configuration, the S1
jumper must be closed.
F.5.6.
Electrical Heater Operation
a)
After unit is turned ON, EH relay will be ON when EH signal is powered ON and EC motor RPM>300.
b)
If EC motor fails or EC motor RPM is lower than 300 RPM, EH relay is opened at once.
F.5.7.
Low Temperature Protection of Indoor Coil in Winter
This is frost protection for when the unit is off to prevent water in the coil and room from freezing.
Unit is in Standby Mode
If Ti1
≦
35.6 ºF for 2 minutes, report error code and Buzzer is beeping.
