Honeywell W7620 - Manual (Page 3)

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
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