DriSteem Vapor-logic3, Инструкция по установке и эксплуатации

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16
Sensing devices and humidity control.
Installation
Important to properly place sensing devices
Humidity sensing devices must be properly placed to
achieve accurate humidity control. A typical small air
handling system is shown in the drawings on Pages 17
and 18 (Figures 17-1 and 18-1). For the best control,
place the humidity sensing device in the center of a
room, or just inside the return air duct (location “A”).
These locations will provide the least amount of
variation caused by air flow patterns and room
temperature. Placement of the duct humidity sensing
device within the outlet of the air handler (location “D”)
is ideal for duct high limit control, but the actual
placement must be downstream from dispersion tubes a
sufficient distance to ensure steam absorption has taken
place. Accurate control of temperatures in rooms and
ducts is also very important to improve control of
relative humidity.
Other factors that affect humidity control
Unsatisfactory humidity control may involve more than
just the controller’s capability to control the system.
Other factors that play an important role in overall
system control are:
•
Size of the humidification system relative to load
• Overall system dynamics associated with moisture
migration time lags
• Accuracy of humidistats and humidity transmitters
and their location
• Dry bulb temperature accuracy in space or duct
• Velocities and air flow patterns in ducts and space
environments
• Electrical noise or interference
Installation:
Sensing devices and humidity control
VL3-IOM-0301-METRIC.pdf 20 11/19/2009 9:22:37 AM