The W7620
Single
Zone Control System is Honeywell’s
new
line
of single
zone
control
products. The W7620,
can conveniently monitor and
control
individual HVAC
zone equipment.
System features include CNAP (Control Network
Automation Protocol) communication, application
flexibility, DDC (Direct Digital Control), network
integration, easy installation and programming, and
increased
equipment reliability.
The basic
W7620
Single
Zone
Controller has built-in
capability to process
I/O
(Input/Output) data,
run
DDC
programs, and communicate along with other devices on
the CNAP
network.
See W7620 family photo.
The W7620
Single
Zone
Controller is a DDC device.
DDC has a control loop which periodically updates
the
outputs
as
a
function
of
a
set of measured inputs and
a
given set of algorithms.
The
advantages of DDC
are:
Control
The W7620
Single
Zone
Controller provides sophisticated
control loops for accurate control of single zone equipment
that prevents
temperature
droop and provides greater
comfort
in
the
zone.
Maintainability
Use of a single programmed computer reduces
requirements for calibration checks because
there
are
fewer interconnected analog components. Periodic
recalibration is automatically
performed.
Reliability
EEPROM (Electrically Erasable Programmable Read
Only Memory) and EPROM
(Erasable
Programmable
Read Only Memory) hold the control program and
parameters
eliminating
the
need
for a
battery.
Communlcatlon
Networking controllers together on
a
RS-485
network
using
CNAP software provides information for integration
of control functions, monitoring, trending, alarming, and
report
generation.
The W7620
Single
Zone
Controller can be applied
in
a
stand-alone environment with distributed zone control
and
hard-wired time-of-day
functionality
It
can
also be
applied as part of
a
networked
system via connection
to
the RS-485 CNAP network. The CNAP
network
enables
communication to multiple
W7620
Zone
Controllers as
well
as
to other
controllers,
such as the
W7600
Control
Module, 47640 NIU or a
Q7650
PC Interface Card in
a PC with ZM7603 Remote Monitoring
software.
Refer
to the ZM7601 Configuration Tool/ZM7603 Remote
Monitoring
software
specification
sheet,
Form 63-4272,
for
a
more detailed description.
Through the CNAP network, the controller can be
provided with information
specific
to its controlled
zone
only,
or
with information necessary for
a
group of
zone
controllers. ZM7601/ZM7603 software
can,
in
turn,
be
provided
with periodic information on any controller data
for
monitoring, data gathering, or report generating. See
Figure 1.
The W7620 Zone Control System was designed for
application flexibility.
Simply
by changing
the
algorithm
which is stored in EBPROM and by
determining
the
input
and
output requirements, the same
W7620
controller
can
be applied in a variety of applications.
‘Ike W7620 Baseboard provides input dedicated to the
T7660 Space Temperature Sensor (space temperature,
remote
setpoint,
bypass switch with LED feedback, and
CNAP communication connections). The baseboard
only
provides four SPST
(Single
Pole, Single Throw) relays.
A variety of small point, single zone or heat pump
applications
can
be met by using only the
W7620.
The
W7621
Input
Board
adds two resistive, one digital,
one AC input, and two voltage
inputs
that
can
be used
for a variety of inputs depending on application. One
W7621 input board
can
be
added
to the
W7620
Zone
controller.
3
63-4224