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In either case, the bypass controller will check to ensure the
fan is off by reading its pressure sensor and damper position. If
the pressure reading is less than 10% of the static pressure set
point and the bypass damper position is less than 25% of the
resistance of the feedback potentiometer for greater than
60 seconds, then the bypass controller assumes the fan is off.
When the fan is off, the bypass controller will drive its damper
to the fully open position. If an invalid feedback resistance
value is detected, the bypass controller will terminate the
calibration. Once at the fully open damper position, the bypass
controller will read the output voltage of the pressure sensor. If
the voltage reads within the range of 1.0 vdc ± 0.1 volt, it
calculates the offset voltage based on the difference between
the output voltage reading and the nominal zero pressure
reading of 1.0 vdc. This value is then stored in non-volatile
memory. If the voltage reading is outside of the tolerance
range, the bypass controller will display “Alarm” in the
commissioning screen. The screen will display “Alarm” until a
successful calibration of the pressure sensor is performed.
When the calibration is completed, the bypass controller will
signal the Linkage Coordinator to return the fan to normal
operation.
Summary of Contents for VVT 33ZC
Page 3: ...3 Fig 2 Bypass Controller Dimensions Fig 1 Bypass Controller Details...
Page 7: ...7 Fig 7 High Torque Actuator Wiring...
Page 8: ...8 Fig 8 High Torque Actuator with Linked Dampers Wiring...
Page 9: ...9 Fig 9 Field Supplied Linked Damper Wiring...
Page 10: ...10 Fig 10 Multiple Field Supplied Linked Damper Wiring...
