Greenheck AMD Installation Manual
®
Vari-Green Constant Volume Controller
for AMS & AMD Damper Series
Installation, Operation and Maintenance Manual
Please read and save these instructions for future reference. Read carefully before attempting to assemble, install,
operate or maintain the product described. Protect yourself and others by observing all safety information. Failure to
comply with instructions could result in personal injury and/or property damage!
These instructions apply to Greenheck’s Vari-Green Constant Volume damper controller. The controller accepts
an analog output from a factory supplied pressure transducer on a Greenheck AMS airflow measuring station
or AMD airflow measuring damper to calculate the realtime volumetric airflow rate (cfm) going through the unit.
Using PID logic the controller then controls the damper’s actuator to achieve a target cfm setpoint. The cfm
setpoint can be established either remotely via an analog input to the controller or locally using touch sensitive
buttons on the cover of the controller.
Table of Contents
General Operation of the Controller .............2
• Setting the Flow Setpoint ...................... 2
• Airflow Output Signal ............................. 2
Document number 479830
Constant Volume
Varigreen Damper
Controller
Controller Display and Interface Buttons ...2-3
Controller Configuration ............................3-6
• Factory Configuration .........................3-4
• Field Configuration ..............................4-6
• Manual Control ......................................6
• Factory Defaults ....................................6
Diagnostic LED ............................................. 7
Wiring of Controller ...................................7-8
Receiving
Upon receiving the control, check to ensure all items are
accounted for by referencing the delivery receipt or packing
list. Inspect each crate or carton for shipping damage
before accepting delivery. Alert the carrier of any damage
detected. The customer will make notification of damage
(or shortage of items) on the delivery receipt and all copies
of the bill of lading which is countersigned by the delivering
carrier. If damaged, immediately contact your Greenheck
Representative. Any physical damage to the unit after
acceptance is not the responsibility of Greenheck Fan
Corporation.
Unpacking
Verify that all required parts and the correct quantity of
each item have been received. If any items are missing,
report shortages to your local representative to arrange for
obtaining missing parts.
Storage
Controls are protected against damage during shipment. If
the control cannot be installed and operated immediately,
precautions need to be taken to prevent deterioration of
the control during storage. The user assumes responsibility
of the control and any accessories while in storage. The
manufacturer will not be responsible for damage during
storage. These suggestions are provided solely as a
convenience to the user.
Indoor
The ideal environment for the storage of controls is indoors,
above grade, in a low humidity atmosphere which is
sealed to prevent the entry of blowing dust, rain or snow.
Temperatures should be evenly maintained between 30° to
110°F (-1° to 43°C). Wide temperature swings may cause
condensation and “sweating” of metal parts. All accessories
must be stored indoors in a clean, dry atmosphere.
Removing from Storage
As controls are removed from storage to be installed in their
final location, they should be protected and maintained in a
similar fashion until the control goes into operation.
1
General Operation of the Controller
The Vari-Green Constant Volume Controller has two operating modes. The controller is factory set to its Flow Control
Mode. In Flow Control Mode the controller will modulate the position of the damper to achieve a target airflow setpoint. The
controller can also be put into Position Control Mode. In Position Control Mode the controller treats the setpoint as a target
damper blade position.
In addition to the two operating modes the controller has a parameter called Setpoint Location that can be configured to
either Remote or Local. The controller ships from the factory with the Setpoint Location set to Remote. In Remote mode the
controller uses a voltage sent to one of its analog inputs to establish the setpoint (see the Setting the Flow Setpoint section
below). When the Setpoint Location is in Local mode the interface on the front cover of the controller is used to establish the
setpoint and the voltage sent to the analog input is ignored.
See the Field Configuration section of this document to learn how to change the Control Mode and Setpoint Location. The
following section assumes that the controller is in the factory default Flow Control and Remote Setpoint Location modes.
Setting the Flow Setpoint
The controller accepts an analog input (configurable for
either 0-10 or 2-10 VDC) that is proportional to a target
volumetric airflow rate (cfm). The voltage corresponding to
the setpoint can be determined using the following formulas:
0 - 10 VDC setpoint
C = Q /(V
2 - 10 VDC setpoint
C = Q /(V
Formula 1
Where:
C = Flow Setpoint (VDC)
Q = Desired Airflow (cfm)
V
= Maximum Velocity as specified at the time the unit
max
was ordered (fpm)
A = Face Area of the Damper (ft2)
max
* A) * 8 + 2
max
* A) * 10
Airflow Output Signal
The controller outputs an analog signal (configurable for
either 0-10 or 2-10 VDC) that is proportional to the real-time
airflow rate (cfm) going through the AMD/AMS. The cfm
corresponding to the voltage output can be determined
using the following formulas:
0 - 10 VDC setpoint
Q = (C * V
max
* A) /10
2 - 10 VDC setpoint
Q = ((C - 2) * V
max
* A) /8
Formula 2
Where:
C = Voltage Output Signal (VDC)
Q = Real-time Airflow (cfm)
V max = Maximum Velocity as specified at the time the unit
was ordered (fpm)
A = Face Area of the Damper (ft2)
Controller Display and Interface
Buttons
There are four touch sensitive buttons on the controller’s
cover that are used to interface with the controller: Back,
Enter, Up and Down (see Figure 2).
Figure 1 - Label affixed to AMS/AMD that
lists the V
Example: The BMS desires 2,000 cfm through a
24 in. x 24 in. AMD-42 that was ordered with a maximum
velocity of 1,000 fpm. Find the voltage setpoint that
corresponds to 2,000 cfm:
C = 2,000 / (1,000 * 4) * 10 = 5 VDC (0-10 VDC)
C = 2,000 / (1,000 * 4) * 8 +2 = 6 VDC (2-10 VDC)
2
and damper area.
max
DisplayBack Button
Up Arrow
Figure 2 - Outside of the controller's cover
Down Arrow Enter Button
Controller Display and Interface Buttons cont...
The controller also has a two line backlit LCD display. By
using the up and down arrows the display can be toggled
through three sets of data:
XXXXX CFM
Setpt XXXXX CFM
• Top Screen: Real-Time CFM and CFM Setpoint
• Middle Screen: Real-Time Velocity (fpm) and Velocity
Setpoint
XXXX FPM
Setpt XXXX FPM
• Bottom Screen: Real-Time Differential Pressure
Measurement and Actuator Position
X.XX in WC
Act XX.X% Open
Figure 3 - Run Mode display screens
Controller Configuration
The Vari-Green Constant Volume Controller is shipped in “Run Mode”. When calculating the airflow rate going through the
AMS/AMD and to control the damper (on AMD models) the controller should be left in run mode. In most cases the controller
should not need to be taken out of run mode. However, a variety of parameters can be adjusted in the field as needed by
opening the controller’s cover and moving the toggle switch into the PROG position (see Figure 2).
When in program mode the display can be toggled through a “Top Level Menu” by using the up and down arrows on the
controller’s cover (see Figure 4). The desired menu item can be accessed by pressing the “Enter” button.
Factory Config
Enter to Select
Field Config
Enter to Select
Manual Control
Enter to Select
Factory Defaults
Enter to Select
Figure 4 - Top level menu in Program Mode.
Factory Configuration
The controller comes from the factory configured with the
physical parameters of the AMD/AMS it was ordered with.
These parameters include:
• Flow Measurement Device – should always be left as
“Diff Pressure”
• The unit’s K & M Values – damper specific constants
used to calculate airflow. These values are set at the
factory and can also be found on the label affixed to
the AMD/AMS (see Figure 1)
• Maximum Pressure – this parameter represents
the top-end of the AMD/AMS pressure transducer
range. The selectable values are: 0.25” wc, 0.5” wc,
1.0” wc, 2.0” wc, 2.5” wc, 3.0” wc, and 5.0” wc. The
maximum pressure is also a configurable value on the
pressure transducer (see the transducer instructions).
The top-end of the controller’s pressure range and
the transducer’s pressure range must match for the
controller to operate properly. They are set at the
factory to the same values.
• Damper Area - the face area of the AMD/AMS
(ft2)
• Maximum Velocity – this parameter represents
the velocity corresponding to a 10 VDC remote
setpoint. This parameter is set by the factory to the
value selected at the time the unit was ordered.
The selectable values are: 500 fpm, 1000 fpm, 1500
fpm, 2000 fpm, 2500 fpm, 3000 fpm, 3500 fpm and
4000 fpm. To achieve optimal accuracy the lowest
value that meets the application should be selected.
Changing the maximum velocity value will affect
the flow setpoint and flow output calculations. See
formulas 1 and 2 on page 2.
• Minimum Velocity – this is the minimum velocity
the unit is designed to accurately measure airflow
and control the damper at. To avoid “hunting” the
controller will treat setpoints below the minimum
velocity as a setpoint of zero. The controller is set to a
value of 300 fpm at the factory.
While the parameters in the factory configuration menu
don’t normally require adjustment, they can be changed by
putting the controller into Program Mode (see above) and
then pressing enter on the “Factory Config” option in the top
level menu. The factory configuration menu structure, see
Figure 5, can be navigated by using the up and down arrows
on the controller’s cover. When the parameter you wish to
adjust is shown in the display press the "Enter" button to
enter the edit mode. The parameter can then be adjusted
by using the up and down arrows (parameter will blink
on display when in edit mode). Once the desired value is
selected press "Enter" again to leave edit mode. Once all of
the parameters have been adjusted press the "Back" button
on the controller to return to the top level menu or return the
slider switch inside the controller to run mode.
3
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