Installation & Operation Manual - Model AVC4000
Contents of this Manual are Subject to Change Without Notification
Page 4
SECTION 1 - INTRODUCTION
The AVC product family integrates a high-performance controller with the revolutionary award
winning AccuValve
®
product. The Engineers at Accutrol have used technology and innovation
to make the AVC AccuValve
®
not only the most advanced airflow control valve in the industry,
but also the most reliable and intuitive airflow control valve available.
1.1
Theory of Operation (Reference the Diagram Below)
The AccuValve
®
divides the airflow into two equal chambers using an airfoil shaped
compression section. Each chamber is comprised of a vortex shedding airflow sensor, a
modulating control blade and a static regain section. As air enters the chambers it accelerates
and compresses, creating an ideal zone for measuring airflow velocity. The vortex shedding
airflow sensors provide a highly repeatable digital pulse-train with a frequency that is directly
proportional to the air flow velocity in each chamber of the AccuValve
®
.
The digital signal generated by each vortex shedding sensor provides a direct measurement of
the volumetric flow rate in each chamber of the AccuValve®. The airflow measurement
provides closed-loop feedback to the ePI
®
controller which modulates the valve actuator to
maintain the desired airflow set point. The airflow set point can be provided from either,
analog input, digital input, communications over BACnet MS/TP or AVC internal program
memory. The AVC also provides analog output signals.
For network communications, the AVC provides an EIA-485 port supporting BACnet MS/TP as a
Full Master Node state machine. Field programming is accomplished through AccuValve
Insight, which is an intuitive user-interface software. Connection between the AVC and
computer is provided through a USB port located on the AVC control module or through an
optional wireless Bluetooth connection.
