AAON VCCX-454 - BD-3 PI Inputs;Outputs Descriptions

35VCCX-454 Controller Technical Guide
INPUTS AND OUTPUTS
BD-3PI Inputs/Outputs Descriptions
OCC/G
When this wet contact input closes, it forces the VCCX-454
Controller into the Occupied Mode. When the OCC/G signal is
removed, the controller reverts to the Unoccupied Mode of operation
if no internal or external schedule has been congured or is in eect
when this occurs.
COOLING/Y
A wet contact closure on this input is used to provide a means for
another building automation system or control device (by others)
to force the unit into Cooling Mode.
HEATING/W
This input only functions in DDC Mode and Thermostat Mode, it
has no function in HP Thermostat mode. A wet contact closure on
this input is used to provide a means for another building automation
system or control device (by others) to force the unit into Heating
Mode.
DEHUM/DH
A wet contact closure on this input is used to provide a means for
another building automation system or control device (by others)
to force the VCCX-454 Controller into Dehumidication Mode.
If dehumidication is congured for all modes on the VCCX-454
then the unit will go into dehumidication mode anytime this input
is activated. If it is congured for vent mode only the heating and
cooling calls will override the dehumidication call.
DISABLE HW/O
This input has dierent functionality for each congured mode:
• DDC Mode
○ This input when activated will force the heat wheel to
stop operating.
• Thermostat Mode
○ This input has no function in this mode.
• HP Thermostat Mode
○ This input when activated along with the Y input will
initiate heat pump heating operation. The thermostat
should be congured for fail-to-cool to properly trigger
this input. Note that the operation of this input in as
fail-to-cool has no relation to whether the actual unit
is built and operated as fail-to-heat or fail-to-cool, this
only relates to how the signals from the HP Thermostat
are interpreted.
SPARE/E
This input only functions in HP T-Stat. When active, this input
will cause the emergency heat to operate on the unit if available.
Activation of this input will also disable any other heat mode that
may be currently commanded.
SAT RESET
This input only functions in DDC mode. If a remote supply air
temperature reset signal is congured as the reset source, this input
can be used to accept a congurable voltage input between 0-10
VDC (direct or reverse acting) to reset the Supply Air Temperature
Setpoint.
SAF SPEED
This input only functions in DDC mode. When enabled, the SAF
will operate as if it is not being overridden by the 3PI if the range is
0 to 1VDC. The SAF will operate at min speed if the input is in the
range of 1VDC to 2VDC. The SAF speed will vary from minimum
to maximum as this input varies from 2VDC to 10VDC.
If the BACnet override is enabled, it will have precedent over this
input.
RAF SPEED
This input only functions in DDC mode. When enabled, the RAF
will operate as if it is not being overridden by the 3PI if the range
is 0 to 1VDC. The RAF will operate at min speed if the input is
in the range of 1VDC to 2VDC. The RAF speed will vary from
minimum to maximum as this input varies from 2VDC to 10VDC.
If the BACnet override is enabled, it will have precedent over this
input.
ECON POS
This input only functions in DDC mode. When enabled, the ECON
POS will operate as if it is not being overridden by the 3PI if the
range is 0 to 1VDC. The ECON POS will operate at min damper
position if the input is in the range of 1VDC to 2VDC. The OA
damper will vary from closed to full open as this input varies from
2VDC to 10VDC.
If the BACnet override is enabled, it will have precedent over this
input.