WattMaster WM-WCC3-TGD-01B - Manual (Page 773)

Operator Interface
VAV/Zone Controller Technical Guide
5
The following inputs and outputs are available on the VAV/Zone Con-
troller and the OE322 Output Expansion Board that can be added by
connecting it to the main controller board expansion port. For component
locations of the inputs on the VAV/Zone Controller see Figure 3. For
wiring of inputs and outputs see Figures 4-9.
VAV/Zone Controller Analog Inputs
Input #1: Space Temperature
The Room Sensor that reads space temperature is attached to this input.
The Sensor connects via a 2- or 3-wire cable to the VAV/Zone Controller.
If the optional push-button override sensor is installed, this input will
detect user overrides from unoccupied back to occupied operation for
a user adjustable amount of time.
NOTE: When a push-button override is detected, the VAV/Zone
Controller will automatically go into override mode even
if it is already in an occupied mode.
Input #2: Airfl ow Sensor
If the VAV/Zone Controller is to be confi gured for pressure independent
operation, you need to install the OE274 Airfl ow Sensor and connect the
modular plug from the pressure sensor to this input. The pressure signal
from the Airfl ow Sensor is used for CFM (airfl ow) calculations. If an
OE274 Airfl ow Sensor is attached to this input, the VAV/Zone Controller
can be programmed for pressure independent operation.
NOTE: VAV/Zone Controllers will automatically operate as Pres-
sure Independent if the “Box Size Constant for airfl ow
@ 1” WG” is greater than 0 CFM.
Input #3: Aux1 - Room Sensor with Slide
Adjust
If the optional slide adjust sensor is installed, the slide adjust will
offset the heating and cooling setpoints by a user-adjustable amount
of degrees.
Input #4: Aux2 - Discharge/Duct Air
Temperature Sensor
A Discharge/Duct Air Temperature Sensor can be connected to these
terminals. It should be mounted in the supply duct close to the terminal
unit where the VAV/Zone Controller is installed. This sensor can be
used for monitoring purposes in place of the Supply Air Temperature
Broadcast from the MCD; otherwise, the Discharge Temperature will
always read the same as the Supply Air Temperature.
NOTE: 1. All temperature sensors must be Thermistor Type
III which provide 77.0 ºF @ 10K Ohms Resistance.
2. The Supply Air Temperature Broadcast from the MCD
must be in an XXX.X format, one decimal place.
Other Controller Connections
Expansion Board Modular Connector
This modular connector is used to connect the optional OE322 Output
Expansion Board to the VAV/Zone Controller. These boards are only
required when electric or hot water heating and/or fan terminal control
is required. The Expansion Boards are not required for cooling only
terminal units.
Actuator Modular Connector
This modular connector is used to connect a modular cable from the
VAV/Zone Controller to a tri-state actuator.
24 VAC Power Terminal Block
This two pole terminal block is used to wire the 24 volt power to the
VAV/Zone Controller. If desired, a single transformer can be used to
power multiple VAV/Zone Controllers together or a separate transformer
can be used for each controller.
WARNING: If multiple controllers are to be wired to the same
transformer, polarity must be observed or damage
to the controller will result.
Communications Terminal Block
This three pole terminal block is used for connecting the communica-
tions wiring between each VAV/Zone Controller to the Satellite, Power/
Comm board, or other controller on the local communications loop.
Communications wiring should be 18 gauge 2 conductor twisted pair
with shield, Belden #82760 or its equivalent.
Optional - OE322 Expansion Board
As previously stated, when control of a fan or if heating is required, the
OE322 Output Expansion Board must be used.
Relay Output #1 - Fan Enable
The fi rst expansion relay on the Output Expansion Boards is used for
enabling the fan for Series or Parallel Fan Terminal Units.
Relay Output #2 - Stage 1 Heating
If you have at least one stage of auxiliary heating, this is the relay used
to energize the 1st stage of terminal unit heating. This heating stage can
either be used with electric heat or On/Off hot water valve control. For
3 stage heating, this relay output would be energized for the 1st and 3rd
stage of heat. See the section that follows for more information regarding
3 stage heating applications.
Relay Output #3 - Stage 2 Heating
If you have two stages of auxiliary heating, this relay controls the 2nd
stage of electric heat. For 3 stage heating, this relay output would be
energized for both the 2nd and 3rd stage of heat. See the following section
for more information regarding 3 stage heating applications.
Controller Inputs and Outputs