WEBVISION™
95-7769—01
54
Configuring Fan Coil Unit
Controllers (FCU)
Description
The W7752 D, E, F, and G Controllers are communicating
mains-powered Fan Coil Unit Controllers in the Excel 10
product line. They cover a wide range of fan coil control
applications. The controllers can operate as stand-alone units
or networked using the standard Echelon L
ON
W
ORKS
bus.
Interfaces are provided for a wide range of actuator types.
Heating systems can be water or electric, and cooling
systems can be chilled water supply or compressors.
Extensive timing and interlock features make the W7752
especially suitable for systems using electric heat and
compressors.
Features
• LonMark HVAC profile 8020.
• Stand-alone operation or on high speed 78 kilobit LON
network.
• Uses Echelon LonTalk protocol.
• Direct connection of thermal actuators.
• Direct connection to fan switch.
• Direct connection to electric heat.
• Factory-configured default parameters.
• Wide range of supported valves and actuators.
• Interlocks and time delays to protect equipment.
• Slim design fits into narrow fan coil units.
• Terminations all on one side allow controller to be
positioned at back of fan coil unit.
• Power supplied by power mains.
FCU Controller Models
Table 29 lists the FCU Controller models.
The W7752D,E,F and G are LonMark compliant Fan Coil Unit
Controllers in the Excel 10 family product line. These
controllers provide room temperature control for two and four
pipe fan coil units with optional electric heating coils
W7752D,F) and can control single, two or three speed fans.
The controller is provided with default configuration settings
from the factory and is fully operable on installation. Using
standard Echelon configuration tools, the controller can be
configured with job-specific settings. A variety of optional wall
modules interface with the FCU controllers and provide any or
all of the following: setpoint adjustment, fan speed
adjustment, and occupancy bypass button. All wall modules
include a space temperature sensor, however a remote
C7068A return air sensor can also be used.
Supported Output Types
Table 30 lists the supported output types for the FCU
Controller.
Navigating to FCU Pages
Go to the
Devices
tab. Expand the list of devices on the left
pane (listed under WebVision). Select a device to view its
properties.
Sequences
Heat and cool sequences can be selected to be active or not
active, giving a total of eight different sequence options (each
can be with or without fan control):
• Heat only
• Cool only
• Heat/cool changeover
• Heat and cool sequence
• All the above with electric reheat
Modes of Operation
The controller has the following modes of operation:
•
Occupied mode
This is the normal operating condition for a room or zone
when it is occupied. The controller can be switched into
this mode by a network command, by the room occupancy
sensor, or by a bypass button on the wall module. In the
occupied mode the fan is controlled by the setting of the
fan speed switch on the wall module or by the control algo-
rithm when the switch is set to
auto
. The fan can be
configured to remain on or turn off during the zero energy
band.
•
Standby mode
The standby mode saves energy by reducing heating or
cooling demand during periods where the room is tempo-
rarily unoccupied. In this mode the fan is switched off
during the zero energy band.
•
Unoccupied mode
This mode is used for longer unoccupied periods, such as
at night or during weekends and holidays.
•
Window open
The controller is configured for window open detection, the
controller automatically disables heat and cool control until
the window is closed again. Frost protection remains
active.
•
Frost protection
If the temperature drops below 46 °F (8 °C), the controller
enables the heating circuit as frost protection.
Table 29. FCU Controller Models.
OS Number
Power Input
Reheat Delay
W7752D2xxx
230 Vac
YES
W7752E2xxx
230 Vac
NO
W7752F2xxx
115 Vac
YES
W7752G2xxx
115 Vac
NO
Table 30. FCU Controller Output Types.
Output
Options
Heating
Floating, thermal, PWM, on/off, multi-
stage electric
Cooling
Floating, thermal, PWM, on/off, multi-
stage compressor
Fan
On/Off, 2-speed, 3-speed
Electric Reheat
On/Off