Orion System VCM-X Modular E-BUS - Manual (Page 15)

VCM-X Modular E-BUS Controller Technical Guide
INSTALLATION & WIRING
15
SAT & RAT Sensor Wiring
Figure 11: OE231 – Supply Air and Return Air Temperature Sensor Wiring
Mount In HVAC
Unit Supply
Air Duct
Mount In HVAC
Unit Return
Air Duct
Supply Air Temperature Sensor
Return Air Temperature Sensor
Be Sure The Jumper Is Set For THERM
On AI2 & AI3 For Supply
& Return Air Temperature Sensors
When Used
Note: The Supply Air Temperature Sensor Always
Wires To The AI2 Input On The VCM-X E-BUS
Controller. It Never Wires To The MODGAS Or MHGRV
Controllers As It Did The Previous VCM Product.
AI2
AI3
GND
GND
VCM-X E-BUS
Controller
AI1
AI1 SET
AI2 SET
AI3 SET
AI4 SET
AI5 SET
AI7 SET
AI2
AI3
AI4
AI5
AI7
Supply Air & Return Air Temperature
Sensor
The OE231 Supply Air & Return Air Temperature Sensors must be
wired as shown in Figure 11 below for proper operation. The Supply
Air & Return Air Temperature Sensors are 10K Type III thermistor
sensors. The Supply Air Temperature Sensor should be mounted in the
unit discharge plenum or in the supply air duct. The Return Air Tem-
perature Sensor should be mounted in the return air duct. If the system
has a Zoning Bypass Damper installed, be sure the return air sensor is
located upstream of the bypass duct connection.
NOTE: Previously, if your AAON
® HVAC unit used the AAON ®
MODGAS Controller and/or the AAON ® MHGRV Controller, the
Supply Air Sensor had to be wired to one of these controllers. This
is no longer the case. The Supply Air Temperature Sensor must
always be connected to the VCM-X E-BUS Controller unless you are
using the AAON
® MODGAS and/or AAON ® MHGRV Controllers
as stand-alone.