Orion System MUA II Controller - Manual (Page 9)

VAV/CAV Controller
Technical Guide
9
Space Temperature Sensor
A Space Temperature Sensor is used with the MUA II controller to
provide for Supply Air Temperature Reset. At a specified Space Tem-
perature Setpoint the Supply Air Setpoint will be reset towards the
Maximum Supply Air Temperature Setpoint. For more information on
the operation of this sequence see the Sequence Of Operation section of
this manual. This sensor is a 10K Type III thermistor sensor. See Fig-
ure 8 for complete sensor wiring details.
Wiring Details
GND
TMP
Space Temperature Sensor
GND
INPUTS
GND
AOUT1
AOUT2
GND
+VDC
AIN1
AIN2
AIN3
AIN4
AIN5
AIN7
MUA II Unit Controller Board
Figure 8: Space Temperature Sensor Wiring
GND
INPUTS
GND
AOUT1
AOUT2
GND
+VDC
AIN1
AIN2
AIN3
AIN4
AIN5
AIN7
Mount In MUA
Unit Supply
Air Duct
Supply
Air Temperature
Sensor
MUA II Controller Board
Figure 9: Supply Air Temperature Sensor Wiring
Supply Air Temperature Sensor
The Supply Air Temperature Sensor should be mounted in the unit
discharge plenum or in the supply air duct.
The Supply Air Temperature Sensors are 10K Type III thermistor sen-
sors.
For systems that are only using the MUA II controller and are not
supplied with The MODGAS II or MHGRV II controllers, the Supply
Air Temperature Sensor must be wired as shown in the illustration
below for proper operation of the controller. See Figure 9 for detailed
sensor wiring. The exception to this is when the MODGAS II and/or the
MHGRV II controllers are also being used on the HVAC unit the MUA
II controller is installed on. See the Caution note regarding this
configuartion that follows.
Caution: If your HVAC unit is supplied with the
MODGAS II controller with or without an
MHGRV II controller, the Supply Air
Temperature Sensor must always be wired to the
MODGAS II controller. If your HVAC unit is
supplied with only the MHGRV II controller, the
SupplyAir Temperature Sensor must be
connected to the MHGRV II controller, not the
MUA II controller. If you have either of these
controllers on your HVAC unit and connect the
Supply Air Temperature Sensor to the MUA II
controller, your controls will not function
correctly.
See the MODGAS II and/or the MHGRV II Technical Guide(s) for
Supply Air Temperature Sensor wiring terminations and information.