NEED AHU (BV1)
The Need AHU Start value object is set to
TRUE (1)
for any of the following conditions.
l
The system mode is
UNOCCUPIED
and the Cooling loop or the Heating loop is
greater than 100% for longer than 10 minutes.
l
The system mode is
OCCUPIED
or
STANDBY
.
l
Either of the Motion Override or Local Override variable objects are
TRUE (1)
.
The Need for AHU Start object changes to
FALSE (0)
when both loops drop below 5% and
the system mod is not
OCCUPIED
or
STANDBY
and both override variable objects are
FALSE (0)
.
NEED COLDER SUPPLY (BV2)
The Need Colder Supply value object is set to
TRUE (1)
when the system mode is
STANDBY
or
OCCUPIED
and the Cooling loop is greater than 95% for 30 minutes. The
indicator changes to
FALSE (0)
when the Cooling loop falls below 90% or when the system
mode is
UNOCCUPIED
.
NEED MORE STATIC (BV3)
The Need More Static value object is set to
TRUE (1)
when the controller has attempted to
drive the damper fully open for longer than 2 minutes 30 seconds and any of the following are
TRUE (1)
.
l
The system mode is
OCCUPIED
or
STANDBY
.
l
Either of the Motion Override or Local Override variable objects are
TRUE (1)
.
When any of these conditions are no longer true, the indicator changes to
FALSE (0)
.
NEED HOTTER SUPPLY (BV7)
The Need Warmer Supply value object is set to
TRUE (1)
when the system mode is
STANDBY
or
OCCUPIED
and the Heating loop is greater than 95% for 30 minutes. The
indicator changes to
FALSE (0)
when the Heating loop falls below 90% or when the system
mode is no longer
OCCUPIED
.
Damper operation
Damper movement is determined by comparing the actual airflow reading to the airflow
setpoints. If the actual airflow is within 5% of the setpoint, no damper action is initiated.
Once within the 5% deadband, the actual airflow must be outside a 7% deadband before
damper position changes.
To improve stability near setpoint, the damper motor is pulsed when the actual flow rate is
within 15% of the requested flow rate. The pulse rate is 5 seconds and the duty cycle is
controlled by analog variable MOTOR PAUSE. In addition, the motor will pause for 10
seconds before the damper changes direction.
SimplyVAV
Section 7: Sequences of operation
Revision H
55
Summary of Contents for SimplyVAV BAC-8001
Page 1: ...SimplyVAV Application and Installation Guide Revision H ...
Page 12: ...Section 1 About the controllers KMC Controls Inc 12 Revision H ...
Page 48: ...Section 6 Application drawings KMC Controls Inc 48 Revision H ...
Page 62: ...Section 7 Sequences of operation KMC Controls Inc 62 Revision H ...
Page 72: ...Appendix A K factors KMC Controls Inc 72 Revision H ...