APPENDIX C - VCB-X BACnet
®
VCB-X Controller Field Technical Guide
100
VCB-X BACnet
®
Parameters
BACnet
®
Properties for the VCB-X Controller
Parameter
Object
Description
Limits
CO
2
Maximum
Setpoint
AV:50
This is the CO
2
level at
which the Economizer Min
Damper Position will be
reset to the Economizer
Max Position in High CO
2
. In between the Min and
Max CO
2
levels the Econo-
mizer Min Damper Position
will be proportionally reset
between the con
fi
gured Min
Damper Position and the
Max Position in High CO
2
.
0
2000
Indoor
Humidity
Setpoint Low
Reset Limit
AV: 51
On indoor controlled (non
MUA) units, this is the Hu-
midity setpoint that initiates
Dehumidi
fi
cation. During
Coil Temp Reset, this is the
lowest Space RH value that
corresponds to the High
Coil Temp Setpoint.
0
100
Indoor
Humidity
Setpoint High
Reset Limit
AV:52
During Coil Temp Reset,
this is the highest Space
RH value that corresponds
to the Low Coil Temp
Setpoint.
0
100
Duct Static
Pressure
Setpoint
AV:53
Current Static
Pressure Setpoint.
.10
3.0
Duct Static
Pressure
Control
Deadband
AV:54
Value above and below
the Duct Static Pressure
Setpoint where no control
change occurs.
.01
.5
Building
Pressure
Control
Setpoint
AV:55
Building
Pressure Setpoint.
-.20
.20
Building
Pressure
Control
Deadband
AV:56
Value above and below the
Building Pressure Setpoint
where no control change
occurs.
.01
.1
Head
Pressure
Setpoint in
Cooling Mode
AV:57
This is the Head Pressure
Setpoint the unit will con-
trol to in the
Cooling Mode.
240
PSI
420
PSI
Head Pressure
Setpoint in
Reheat
Mode
AV:58
This is the Head Pressure
Setpoint the unit will
control to in the
Dehumidi
fi
cation
Reheat Mode.
240
PSI
420
PSI
Minimum
Outdoor Air
CFM
AV:59
Minimum Outdoor Air
fl
ow
CFM Setpoint
.10K
200K
BACnet
®
Properties for the VCB-X Controller
Parameter
Object
Description
Limits
Outdoor Air
CFM
Proportional
Window
AV:60
Controls rate of change
for damper signal. As OA
CFM moves further from
setpoint within this window,
the damper makes a larger
change.
10
9999
SZ VAV Fan
Speed Integral
AV:61
The Integral Constant for
Single Zone VAV Fan
Control.
0
10
Schedule
Force
AV: 62
0 = Auto (uses controller’s
schedule)
1 = Forced
Occupied
2 = Forced Unoccupied
0
2
HVAC Mode
Override
AV: 63
Overrides normal controller
operation in order to force
the unit into this desired
mode. Con
fi
guring for
“Auto” will restore normal
unit control of the mode of
operation.
0=Auto
1=Vent
2=Cool
3=Heat
4=Vent
Dehum.
5=Cool
Dehum.
6=Heat
Dehum.
Fan VFD
Override
AV: 64
Override to force the VFD
to this percentage speed.
Con
fi
guring “Auto” will
restore normal unit control
of the VFD speed.
0%
100%
Auto=65535
Outdoor Air
Damper
Override
AV: 65
Overrides all other Outdoor
Air Damper position
commands so as to maintain
this
fi
xed position.
Con
fi
guring for “Auto” will
restore normal unit control
of the Outdoor Air Damper/
Economizer operation.
0%
100%
Auto=65535
Warm-Up
Supply Air
Temperature
Setpoint
AV: 66
Heating will be controlled
to this Supply Air Setpoint
during Warm-Up.
40
240
Cool-Down
Supply Air
Temperature
Setpoint
AV: 67
Cooling will be controlled
to this Supply Air Setpoint
during Cool-Down.
30
80
Cooling
Enabled
Status
BI: 1
Status that indicates
Mechanical Cooling is
enabled based on the
Cooling Lockout.
Heating
Enabled
Status
BI: 2
Status that indicates that
Mechanical Heating is en-
abled based on the Heating
Lockout.
Economizer
Enabled
Status
BI: 3
Status that indicates
the Economizer is enabled
based on the Economizer
Enable Setpoint.
Revised 4/10/14
