Honeywell W7750A User Manual
EXCEL 10 W7750A,B,C CONSTANT VOLUME AHU CONTROLLER
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PWM
Pulse Width Modulated output; allows analog
modulating control of equipment using a digital output
on the controller.
on the controller.
RTD
Resistance Temperature Detector; refers to a type of
temperature sensor whose resistance output changes
according to the temperature change of the sensing
element.
according to the temperature change of the sensing
element.
Subnet
A L
ON
W
ORKS
Bus segment that is separated by a
router from its Q7750A Zone Manager.
TOD
Time-Of-Day; the scheduling of Occupied and
Unoccupied times of operation.
TPT
Twisted Pair Transceiver.
VA
Volt Amperes; a measure of electrical power output or
consumption as applies to an ac device.
Vac
Voltage alternating current; ac voltage rather than dc
voltage.
VAV
Variable Air Volume; refers to either a type of air
distribution system, or to the W7751 Excel 10 VAV Box
Controller that controls a single zone in a variable air
volume delivery system.
Controller that controls a single zone in a variable air
volume delivery system.
VOC
Volatile Organic Compound; refers to a class of
common pollutants sometimes found in buildings.
Sources include out-gassing of construction materials,
production-line by-products, and general cleaning
solvents. A VOC is occasionally used as a measure of
indoor air quality.
Sources include out-gassing of construction materials,
production-line by-products, and general cleaning
solvents. A VOC is occasionally used as a measure of
indoor air quality.
W7750
The model number of the Excel 10 CVAHU
Controllers (also see CVAHU).
W7751
The model number of the Excel 10 VAV Box
Controllers (also see VAV).
Wall Module
The Excel 10 Space Temperature Sensor and
other optional controller inputs are contained in the
T7770 or the T7560A,B Wall Modules. See Application
Step 5. Order Equipment for details on the various
models of Wall Modules.
T7770 or the T7560A,B Wall Modules. See Application
Step 5. Order Equipment for details on the various
models of Wall Modules.
XBS
Excel Building Supervisor; a PC based tool for
monitoring and changing parameters in C-Bus devices.
Construction
Controllers
The Excel 10 W7750 Controller is available in three different
models. The W7750A Model, which is a low cost controller
made for simple single zone air handlers and heat pump
controls. The W7750B,C Models are intended for more
complex applications.
models. The W7750A Model, which is a low cost controller
made for simple single zone air handlers and heat pump
controls. The W7750B,C Models are intended for more
complex applications.
The W7750B,C Models use Triacs for their digital outputs,
where as the W7750A Model uses dry-contact relays. The
W7750C Model also has three analog outputs available on
terminals 16, 17 and 18.
where as the W7750A Model uses dry-contact relays. The
W7750C Model also has three analog outputs available on
terminals 16, 17 and 18.
All wiring connections to the controller are made at screw
terminal blocks. Connection for operator access to the
L
terminal blocks. Connection for operator access to the
L
ON
W
ORKS
Bus is provided by plugging the SLTA connector
cable into the L
ON
W
ORKS
Bus communications jack.
The W7750A,B,C Models consist of a single circuit board that
is mounted in a sheet metal subbase and protected by a
factory snap-on cover. The three controllers have the same
physical appearance except for terminals 16 through 20
(W7750A) and different labels next to the wiring terminals
(see Fig. 3, 5 or 6). Wires are attached to the screw terminal
blocks on both sides of the controller. The controllers mount
with two screws (see Fig. 4 or 7). The W7750 can also be
mounted using DIN rail. To mount the W7750 on DIN rail,
purchase two DIN rail adapters (obtain locally) part number
TKAD, from Thomas and Betts, see Fig. 8, then snap onto
standard EN 50 022 35 mm by 7.5 mm (1-3/8 in. by 5/16 in.)
DIN rail. DIN rail is available through local suppliers.
is mounted in a sheet metal subbase and protected by a
factory snap-on cover. The three controllers have the same
physical appearance except for terminals 16 through 20
(W7750A) and different labels next to the wiring terminals
(see Fig. 3, 5 or 6). Wires are attached to the screw terminal
blocks on both sides of the controller. The controllers mount
with two screws (see Fig. 4 or 7). The W7750 can also be
mounted using DIN rail. To mount the W7750 on DIN rail,
purchase two DIN rail adapters (obtain locally) part number
TKAD, from Thomas and Betts, see Fig. 8, then snap onto
standard EN 50 022 35 mm by 7.5 mm (1-3/8 in. by 5/16 in.)
DIN rail. DIN rail is available through local suppliers.
A channel in the cover allows the controller status LED to be
visible when the cover is in place. There are no field-
serviceable parts on the circuit board and, therefore, it is
intended that the cover never be removed.
visible when the cover is in place. There are no field-
serviceable parts on the circuit board and, therefore, it is
intended that the cover never be removed.
The W7750A,B,C can be mounted in any orientation.
Ventilation openings were designed into the cover to allow
proper heat dissipation regardless of the mounting orientation.
See Fig. 4 and 7.
Ventilation openings were designed into the cover to allow
proper heat dissipation regardless of the mounting orientation.
See Fig. 4 and 7.
The input/output and control differences between the two
models are summarized in Table 2. The I/O points in Table 2
are the free I/O points that are not reserved for Wall Module
use.
models are summarized in Table 2. The I/O points in Table 2
are the free I/O points that are not reserved for Wall Module
use.
Table 2. List of Differences in W7750A and W7750B,C Controllers.
*The T7770 or the T7560 Wall Modules includes I/O points for
two analog inputs for the space temperature and the setpoint
knob, a digital input for the Bypass pushbutton, and a digital
knob, a digital input for the Bypass pushbutton, and a digital
output for the LED Bypass Indicator. These W7750 I/O
points are configurable, but are normally used for the Wall
Module.
points are configurable, but are normally used for the Wall
Module.
W7750A Model
W7750B,C Models
Digital Outputs
Six Relay Outputs
Eight Triac Outputs
Digital Inputs
Two
Four
Wall Module
One*
One*
Analog Outputs
None
Three 4 to 20 mA Outputs (W7750C only)
Analog Inputs
One (Resistive Input Only) Four (Two Resistive and two Voltage/Current Inputs)
DC Power
None
20 Vdc available to power optional sensors
Floating (Series 60) Control Economizer Only
Heating, Cooling, and/or Economizer
PWM Control
None
Heating, Cooling, and/or Economizer