Specifications

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The Fan will operate when the cooling or heating PID value is greater than 10% for zone control
applications, if it is set to cycle with the compressors.
For Discharge Air Control (DAC) applications, the fan input percent is acquired from the PID
static pressure control logic. DAC fan operation will run only during occupancy and for the unit
being configured for discharge air control.
The fan may be configured for continuous operation during occupancy or for operation during
compressor operation.
Fan Override
The fan will operate when the override mode is initiated.
VFD Control
The following applies for VFD Control:
• Variable Frequency Drive fan control requires a static pressure measurement.
• The static pressure sensor uses inches of water column as the unit of measure.
• The static pressure sensor is configured for IN-1 port of the FHP-583.
• The static pressure set-point is user configurable and it is used by the static pressure PID
control.
• The minimum VFD fan speed is user configurable and is set during the test and balance
phase of commissioning phase.
• A static pressure measurement may be compensated with a user configurable value.
• A high static pressure alarm will be generated for a static pressure exceeding the
maximum static pressure trip point for a minimum of 10 minutes.
• The static pressure sensor will be range-validated and a sensor failure alarm will be
generated for a missing sensor.
• The VFD analog output port AN-1 is shared with the mixed air output, therefore mixed Air
and VFD operation operations may not be simultaneously configured.
• The VFD output may be switched to a constant value for a smoke event if enable.
Fan Operation during Smoke Event
Under most circumstances during a smoke event the fan will be commanded off however there
are conditions where fan operation may be required to prevent smoke infiltration by providing