Siemens QFA1000 Technical Instructions

QFA1000, QFA1001
Room Hygrostats
Description
Features
Application
Product Numbers
QFA1001
The room hygrostats are used for controlling and monitoring relative humidity in
ventilation or air conditioning facilities. They ensure room humidity control within the
selectable range of 30 to 90% relative humidity by controlling humidification or
dehumidification equipment. They can also be used for monitoring minimum or
maximum humidity levels.
• Hygrostat with single-pole microswitch
• Humidity measuring element made of stabilized plastic
• Setpoint knob for the upper switching point
• Mounts directly on the wall or on a recessed conduit box
• For controlling humidification equipment
• For controlling dehumidification equipment
Product Setpoint Setting
Number
QFA1000 30 to 90% rh
QFA1001
1)
The static switching differential is determined at a constant ambient humidity by
turning the setting knob.
The dynamic switching differential is determined by changing the ambient humidity
while maintaining the same setpoint adjustment; only the dynamic switching
differential is of practical value.
Technical Instructions
Switching Differential
Range
Statically
Approx. 4% rh
Document No. 155-708
July 19, 2010
QFA1000
1
Adjustment
Dynamically
6% rh
Siemens Industry, Inc.
Setpoint
Internally
Externally