The VMA
18 Series programmable VAV box controllers are intended for use as
functional replacements for the VMA1410, VMA1415, VMA1420, and the VMA1440 controllers.
VMA1826
controllers are
well-suited for commercial zoning applications and can be used for pressure dependent
VAV box applications where no differential pressure tranduser (DPT) is required.
Note: At Controller Configuration Tool (CCT) 13.0 or later, using Release Mode 10.1, VMA
18 Series controllers can
be configured as either N2 devices or as standard BACnet® MS/TP
devices. This ability provides a potential cost-effective protocol upgrade path for
existing customers and should be considered when you install the controller.
Important: When you receive a VMA18
Series controller from the factory or upgrade
the firmware or main code, the controller defaults to using the MS/TP communications
protocol. The Load Summary screen of CCT shows the connection as Wired Field
Bus, indicating that the MS/TP protocol is in use. If you have an N2
application, the Load Summary screen indicates that you need to switch the
communications protocol to N2.
These VMA
controllers feature an
integral digital pressure sensor, a
damper actuator, and a 32-bit microprocessor. The controller's small package size
facilitates quick field installation and efficient use of space for field replacements,
while still enabling precision control performance.
Note: Connecting an IOM
to the
VMA
via the SA Bus
connection is not supported.
For information about sensor compatibility and replacement, see Sensor replacement and reuse scenarios.