Dear Raghu,
Thanks
Here is I/O summary of the plant.

Digital Input:-
-Selector Switch Auto/Manual
-On Push Button
-Off push button
-Compressor Cut-in press Switch
-Compressor Cut-off press Switch
-Air Comp temp.switch
-Air Comp oil press switch
-Compressor Stage1/2 press. Switch

Digital Output:
-Compressor stage 1 Solenoid
-Compressor stage 2 Solenoid
-LCD
Relays & Contactors:
-Alarm relay
-Safety Circuit Relay
-Solenid 1 Relay
-Solenoid 2 Relay
-Motor safety Relay
-Over current Relay
-Em. Shut down relay
-Air drain Valve relay
-Star-Delta Time Change over relay
-Air Bottles equilising V/v Close relay
-Air Bottles equilising V/v Open relay
-Main Contactor
-Contactor Star
-Contactor Delta

Analog Inputs:-
_Motor winding Temp.
-Air Bottle air Temp
-Air Bottle Air Pressure

Analog output:-
-Air Bottles equilising V/v control signals

Key pad is to be used to change the setting by authorised
person and the operator. Such as: Manual or Automatic operation
Pressure and temperature adjustments etc.


Thanks

Rashu