Справочник Пользователя для Honeywell W7750A
EXCEL 10 W7750A,B,C CONSTANT VOLUME AHU CONTROLLER
25
74-2958—1
Fig. 15. Heat pump with two compressors and auxiliary
heat stage(s).
ECONOMIZER CONTROL
Economizer control is available concurrently with any
configuration in the W7750 when DOs are not all used by the
heating and cooling equipment. Two types of economizer
controls are supported by the W7750 Controller, modulating
control and enable/disable control. Modulating control can be
either Series 60 Floating Control or PWM control (PWM
control is available on the W7750B,C only). A discharge air
temperature sensor is required for modulating economizer
damper control. Enable/disable control is provided to emulate
the Honeywell T7300 thermostat economizer operation,
where a DO tracks the occupancy status of the controller. An
external packaged economizer control then modulates the
dampers. For modulating control, the economizer is enabled
or disabled based on one of ten available strategies (see
Appendix B—Sequences of Operation—Economizer Enable/
Disable Control section, for further details). Fig. 16 illustrates
a system with modulating economizer dampers (see Fig. 29,
31, 32 and 35 in Step 4. Prepare Wiring Diagrams section, for
wiring details).
configuration in the W7750 when DOs are not all used by the
heating and cooling equipment. Two types of economizer
controls are supported by the W7750 Controller, modulating
control and enable/disable control. Modulating control can be
either Series 60 Floating Control or PWM control (PWM
control is available on the W7750B,C only). A discharge air
temperature sensor is required for modulating economizer
damper control. Enable/disable control is provided to emulate
the Honeywell T7300 thermostat economizer operation,
where a DO tracks the occupancy status of the controller. An
external packaged economizer control then modulates the
dampers. For modulating control, the economizer is enabled
or disabled based on one of ten available strategies (see
Appendix B—Sequences of Operation—Economizer Enable/
Disable Control section, for further details). Fig. 16 illustrates
a system with modulating economizer dampers (see Fig. 29,
31, 32 and 35 in Step 4. Prepare Wiring Diagrams section, for
wiring details).
Fig. 16. Economizer control.
PNEUMATIC ACTUATOR CONTROL
The W7750B,C Controller can control pneumatic actuators for
any or all of the three modulating outputs provided by the
control algorithm (heat, cool and economizer). Control of
pneumatic water/steam valves and damper actuators is
provided through a transducer device using either Series 60
Floating Control or PWM DOs. A floating-to-pneumatic, or a
PWM-to-pneumatic transducer is required for each output
signal. The W7750A Controller can drive Series 60 Floating
any or all of the three modulating outputs provided by the
control algorithm (heat, cool and economizer). Control of
pneumatic water/steam valves and damper actuators is
provided through a transducer device using either Series 60
Floating Control or PWM DOs. A floating-to-pneumatic, or a
PWM-to-pneumatic transducer is required for each output
signal. The W7750A Controller can drive Series 60 Floating
Control to modulate cooling valves, heating valves and
economizers. There are no PWM outputs configurable on the
W7750A model.
economizers. There are no PWM outputs configurable on the
W7750A model.
For projects with existing pneumatically actuated reheat
valves, the Excel 10 W7750 Controller output must be
converted to a pneumatic signal using a transducer device
developed for use with Excel 10 Controllers. The transducer is
valves, the Excel 10 W7750 Controller output must be
converted to a pneumatic signal using a transducer device
developed for use with Excel 10 Controllers. The transducer is
MIXED
AIR
AIR
AUXILIARY
HEAT
STAGE(S)
HEAT
STAGE(S)
SHARED
HEAT AND
COOL COIL
HEAT AND
COOL COIL
DISCHARGE
AIR
AIR
+
FAN
FAN
STARTER
STARTER
COMPRESSOR AND
CHANGEOVER VALVE
CHANGEOVER VALVE
COMP 1
COMP 2
CHANGEOVER
RELAY
M17493
EXCEL 10
CVAHU
W7750A,B,C
T7560A,B OR T7770
OUTDOOR
AIR
AIR
RETURN
AIR
AIR
HEAT
COIL
COIL
COOL
COIL
COIL
DISCHARGE
AIR
AIR
-
+
FAN
FAN
STARTER
STARTER
DISCHARGE
TEMPERATURE
SENSOR REQUIRED
FOR ECONOMIZER
CONTROL
TEMPERATURE
SENSOR REQUIRED
FOR ECONOMIZER
CONTROL
M
PWM OR
SERIES 60
FLOATING
MOTOR
SERIES 60
FLOATING
MOTOR
M17494
EXCEL 10
CVAHU
W7750A,B,C
T7560A,B OR T7770