KMC Controls BAC-4000 series, Инструкция по установке, эксплуатации и применению

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fallen to 5%. The controller programming supports both normal and reverse
action valves which can be set from the user interface.
Normal—The valve is closed when the output is inactive and open when
the output is active.
Reverse—The valve is closed when the output is active and open when
the output is inactive.
Modulating valves
On a call for cooling or heating, a modulating valve will modulate from 0 to
100% over the first half (0 to 50%) of the PID loop output controlling the
valve. The AppStat supports both normal and reverse action valves which can
be set from the user interface.
Normal—The valve is fully closed when the output signal is 0 volts and
fully open when the output is 10 volts DC.
Reverse—The valve is fully closed when the output signal is 10 volts and
fully open when the output is 0 volts DC.
Two-pipe water supply temperature evaluation
For two-pipe fan coil units, the AppStat uses the water supply temperature
sensor—input WST–to determine if chilled or hot water is being supplied to
the unit. The water type is determined by comparing the value of the water
temperature sensor input to the room temperature. The AppStat
programming then determines that the water temperature is one of the
following.
Chilled—the water temperature is 10° F below room temperature.
Hot—the water temperature is 10° F above room temperature.
None—the water temperature is within 7° F of room temperature.
If the water temperature is evaluated as None, the AppStat runs the water
evaluation program every six hours. During a water evaluation, the AppStat
opens the valve until a water type is determined or for five minutes,
whichever is reached first. If a water evaluation is not being performed, the
valve remains closed.
The supply water type is stored in multistate variable Water Available.
Installation, Operation, and Application Guide for AppStat Section 5: Sequences of operation
Revision G 71