Condair GS 120 OC, Installation, Commissioning And Service Instructions

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4.2 Selecting the control system
The various control systems
– System 1: Room humidity control
System 1 is suited for air conditioning systems with mainly recirculated air . The humidity sensor
is preferably located in the room itself or in the exhaust air duct.
A1/2 humidity sensor
B1 ventilation interlock
B2 airflow monitor
B3 safety humidistat
PI
E
external continuous controller (e.g. PI-controller)
PID
I
internal continuous controller (PID controller)
Y input signal from A1
Z input signal from A2
A1 humidity sensor
B1 ventilation interlock
B2 airflow monitor
B3 safety humidistat
PI
E
external continuous controller (e.g. PI-controller)
PID
I
internal continuous controller (PID controller)
Y input signal from A1
– System 2: Room humidity control with continuous limitation of the supply air humidity
System 2 is suited for air conditioning systems with a large portion of supply air , low supply air
temperature , post-humidification , or variable airflow volume . If the supply air hum idity exceeds
the preset value, the continuous limitation is effected prior to the room hum idity control.
The humidity sensor (A1) is preferably located in the exhaust air duct or in the room itself. The hu­
midity sensor (A2) for the limitation of the supply air humidity is located in the supply air duct after
the steam distribution pipe. This control system requires the internal PID controller or an external
continuous controller with the option to connect a second humidity sensor.
Attention! The continuous limitation of the supply air humidity is no substitute for the safety humidistat.