Orion System VCM Controller - Manual (Page 35)

VCM Controller
Technical Guide
35
AOUT2 - Duct Static Pressure Control Signal
This voltage signal (0-10 VDC) can be connected to a Supply Fan VFD
or to Proportional Inlet Vanes to control the Duct Static Pressure. This
signal can also be connected to a 0-10 VDC Modulating Zoning Bypass
Damper Actuator to control Duct Static Pressure. When this signal is
used to control a Zoning Bypass Damper Actuator, the Zoning Bypass
Damper Actuator needs to be mechanically configured to close the Zon-
ing Bypass Damper on an increase of the 0-10 VDC output signal. This
is necessary because the signal is Direct Acting and is not configurable
as a Reverse Acting Signal on the VCM controller.
R1 - Supply Fan (Enable)
This is a non-configurable output.
R2 Thru 5 - User Configurable Relays
These relays are configurable by the user. For all the available configu-
ration options see the OE357 4 Relay Output Expansion Board sec-
tion of this manual.
OE354 (4) Analog Input
(1) Analog Output Expansion Board
AIN1 - Outdoor Air Humidity Sensor Input
This input is used to connect an Outdoor Air Humidity Sensor that,
combined with the Outdoor Air Temperature Sensor reading, is used to
calculate a Dewpoint and/or Wetbulb Temperature. Outdoor Air
Dewpoint Temperature is used to activate the Dehumidification Mode
on MUA and CAV configured units which utilize the Dual Damper
Mode (Hood On/Off) control feature. The Wetbulb Temperature is used
for Economizer enthalpy control.
AIN2 – Indoor Air Humidity Sensor Input
The Indoor Air Humidity Sensor is used to activate Dehumidification
Mode on a VAV or CAV unit. The Sensor can be either a Wall Mounted
Space Humidity Sensor or a Return Air Duct Mounted Humidity Sen-
sor.
AIN3 - CO
2
Sensor Input
This Sensor is required if you need to monitor Indoor Air Quality and
modify the Economizer operation based on levels of CO
2
in the space
or building you are monitoring. The CO
2
Sensor can be either a Wall
Mounted CO
2
Sensor or and Return Air Mounted CO
2
Sensor as re-
quired by your specific application.
AIN4 - Building Pressure Sensor Input
This Sensor is only required if you wish to configure the VCM Control-
ler for Building Pressure Control. Building Pressure Control can be
accomplished by using one of two main control methods. One control
method uses the 0-10 VDC signal to control an Exhaust Fan VFD or an
Exhaust Damper Actuator for Direct Acting Pressure Control applica-
tions. In addition, for Reverse Acting Pressure Control applications it
can control an Outdoor Air Damper Actuator. The other available con-
trol method is to configure one of the Output Relays as an Exhaust Fan
output which will activate the Exhaust Fan anytime the Building Pres-
sure is above the Building Pressure Setpoint.
AOUT1 - Building Pressure Control Signal
This voltage signal (0-10 VDC) is used to provide an output signal to a
Building Pressure Control device. The output signal can be connected
to either an Exhaust Fan VFD or an Exhaust Damper Actuator when
Direct Acting Building Pressure Control is required. When Reverse
Acting Building Pressure Control is required, the output signal would
be connected to an Outdoor Air Damper Actuator. When used in this
application the output signal must be configured for Reverse Acting
Operation.
OE355 (4) Analog Output
Expansion Board
AOUT1 – Modulating Heating Signal
This output signal can be configured for either 0–10 VDC or a 2-10
VDC output signal. This signal can be configured for either Direct Act-
ing or Reverse Acting operation. This output signal is used to operate a
Modulating Heating Device to maintain the Heating Supply Air Tem-
perature Setpoint.
AOUT2 – Modulating Cooling Signal
This output signal can be configured for either 0–10 VDC, 2-10 VDC
or 1.5-5.0 VDC output signals. This signal can be configured for either
Direct Acting or Reverse Acting operation. This output signal is used to
operate a Modulating Cooling Device to maintain the Cooling Supply
Air Temperature Setpoint. If your unit uses a Digital Compressor this
must be configured for a 1.5-5.0 VDC output signal.
AOUT3 – Return Air Damper Signal
This output signal is a Direct Acting 0–10 VDC output signal that is
used to modulate a Return Air Damper Actuator in concert with a Re-
turn Air Bypass Damper Actuator for PAC or DPAC control schemes.
AOUT4 – Return Air Bypass Damper Signal
This output signal is a Direct Acting 0–10 VDC output signal that is
used to modulate a Return Air Bypass Damper Actuator in concert with
a Return Air Damper Actuator for PAC or DPAC control schemes.
OE357 (4) Relay Expansion Boards
R6 – R21 User Configurable Relay Outputs
Relays can be configured in any order but we recommend that they be
configured in the following order:
1. Cooling stages
2. Heating stages
3. Warm–up Mode Command (for VAV Boxes)
4. Reversing Valve (for Air to Air Heat Pumps)
5. Reheat
6. Exhaust Fan
7. Pre-Heater (for Low Ambient Protection)
8. Alarm
9. Override
10. Occupied
11. Economizer