Accutrol AccuValve AVT3000, Installation & Operation Manual

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Installation & Operation Manual
- Model AVT3000 & H-AVT3000
Contents of this Manual are Subject to Change Without Notification
Page 4
SECTION 1 - INTRODUCTION
The AVT3000 product family is intended for applications that require accurate and repeatable
airflow measurement with high turn-down with precise closed-loop control using an external PI
controller. The AVT3000 incorporates a state-of-the-art vortex shedding digital transmitter
with an intuitive user-interface software known as the AccuValve Insight.
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 surface and a static regain section. As air enters the chambers it accelerates
and compresses, creating an ideal location 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 pulses generated by each vortex shedding sensor are used to calculate the total
airflow volume flowing through the AccuValve
®
. The transmitter provides a software-
selectable analog output signal that is directly proportional to the total airflow volume
measurement. The airflow volume can also be provided directly to the building management
system’s BACnet MS/TP network by ordering the optional BACnet MS/TP communications
module.