Microprocessor Control Board: Typical Location othe
Opto-Isolators and Triacs
Input Opto-Islators
Alarm Input Opto-Isolator Legend:
Opto
U15
Air Safety Switch
U16
Custom Alarm 1
U17
Custom Alarm 2
U18
Custom Alarm 3
U19
Custom Alarm 4
U20
Humidifier Problem
U21
Filter Clog switch
U22
Main Fan Overload
Note: Use Pin 5 on the input opto-isolator with reference to the V- terminal
for voltage check. The voltage level is 3.3 VDC.
iCOM
Microprocessor Control Board
Purpose
153
Control Training and Service Manual
Output Opto-Isolators and Triacs
Opto
Purpose
U23
Power On
U24
Compressor 2 Overload
U25
Low Pressure Switch 2
U26
High Head Pressure 2
U27
Compressor 1 Overload
U28
Low Pressure Switch 1
U29
High Head Pressure 1