Carrier RTU-MP, Руководство по интеграции

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Installation
16 RTU-MP Controller
•
Heat mode is not active and the time guard between modes equals zero
• If occupied and the SPT >(occupied cool setpoint plus the T56 slider offset)
•
Space Temperature reading is available.
• If it is unoccupied and the SPT > (unoccupied cool setpoint plus the T56 slider offset). The indoor fan will
be turned on by the staging algorithm
•
If economizer is available and active, and economizer open > 85% and SAT > (SAT low limit + 5°F) and
SPT > effective set point + 0.5°F.
○
OR Economizer is available, but not active
○
OR Economizer is not available
• OAT > DX Lockout temperature
If all of the above conditions are met, the compressors will be energized as required, otherwise they will be
de-energized.
There is a fixed 3 minute minimum on time and a 5 minute off time for each compressor output, as well as a
3 minute minimum time delay between staging up or down.
Any time the compressors are running, the RTU-MP will stage down the compressors if the SAT becomes less
than the cooling low supply air setpoint. After a compressor is staged off, it may be started again after a
normal time--guard period and the supply air temperature has increased above the low supply air setpoint.
After a compressor is staged off, it may be started again after a normal time-guard period and the supply air
temperature has increased above the low supply air setpoint.
Economizer
The Economizer dampers are used to provide free cooling and Indoor Air Quality, if optional CO2 sensor is
installed, when the outside conditions are suitable.
The following conditions must be true for economizer operation:
•
Indoor Fan has been on for at least 30 seconds. S Enthalpy is Low if the Enthalpy input is enabled.
•
SAT reading is available.
•
OAT reading is available.
•
SPT reading is available.
•
OAT <= High OAT economizer lockout configuration (default = 75)
•
OAT <= SPT
If any of the mentioned conditions are not true, the economizer will be set to its configured minimum
position. The minimum damper position can be overridden by the IAQ routine described later in this section.
If the above conditions are true, the Economizer Control Master Loop will calculate a damper position value
based on the following calculation:
Damper Position = minimum po PID (SPT - econ setpoint). Econ setpoint is half way between the
effective cool and heat setpoints. If the SAT drops below the cooling low supply air setpoint (+ 5°F), the
economizer will ramp down to minimum position.