Carrier RTU-MP, Руководство по интеграции

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Installation
18 RTU-MP Controller
Indoor Air Quality
If the optional indoor air quality sensor is installed, the RTU-MP will attempt to maintain indoor air quality
within the space at the user-configured differential setpoint by modulating the outdoor air
damper/economizer. The set point is the difference between the indoor air quality and an optional outdoor air
quality sensor.
If the outdoor air quality is not present, then a fixed value of 400ppm is used. The following conditions must
be true in order for this algorithm to run:
•
The mode is occupied.
•
Indoor Fan has been ON for at least 30 seconds.
•
Indoor Air Quality sensor has a valid reading
As air quality within the space changes, the minimum position of the economizer damper will be changed,
thus allowing more or less outdoor air into the space, depending on the relationship of the indoor air quality
to the differential setpoint.
If all the above conditions are true, the IAQ algorithm will run and calculates an IAQ minimum position value
using a PID loop. The IAQ minimum damper position is then compared against the user-configured
economizer minimum position and the greatest value becomes the final minimum damper position of the
economizer output.
If the calculated IAQ minimum position is greater than the IAQ maximum damper position configuration, then
it will be clamped to the configured value.
Dehumidification
The RTU-MP provides occupied and unoccupied dehumidification on units that are equipped with the Carrier
Humidi-MiZer™ option from the factory. This requires a space relative humidity sensor or a humidistat for
control.
The following conditions must be true for the dehumidification control to operate:
• The Outside Air Temperature is greater than the Cooling Lockout Temperature setpoint
•
The Indoor Fan has been ON for at least 30 seconds
• The unit has a valid Supply Air Temperature input
•
The unit has a valid Space Temperature input
• The unit has a valid
Space Relative Humidity Sensor
or
Humidistat
input
•
Heat mode is not active and the time guard between modes has expired
When using a relative humidity sensor to control dehumidification, occupied and unoccupied dehumidification
setpoints are used.
When using a humidistat, the setpoints are not used. The humidistat indicates a high-humidity condition.
When a high indoor relative humidity condition is indicated and the above conditions are satisfied, the RTU-
MP enters the dehumidification mode, energizing the Humidi-MiZer™ output.
The mode continues until the space relative humidity falls below the active setpoint by a 5% fixed Hysteresis
when a humidity sensor is used, or when there is no longer a call for dehumidification where a humidistat is
used.
See the base unit / Humidi-MiZer™ operations manual for additional information.