Honeywell W7752D specifications Control Application, Control Provided

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EXCEL 10 FCU CONTROLLER LNS PLUG-INS USER GUIDE

Control Application

Fan coil unit systems in commercial buildings control room temperature through the control of heat and/or cold water valves and fan speed. Electric reheat coils may also be used in the system. The Excel 10 FCU Controller is located in the FCU and is typically connected to an Excel 10 wall module

which incorporates a temperature sensor, setpoint and fan speed controls, and a bypass or override button. Fig. 2 shows a typical FCU ontrol application.

	window
	contact
e.g. Excel 10 W7754
FCU Controller
Honeywell	Excel 10
D-71101 Schönaich
Made in Germany
	wall module

LonWorks network

Fig. 2. Typical Fan Coil Unit control application

Control Provided

Excel 10 FCU Controllers provide room temperature control for two- and four-pipe fan coil units with optional electric heating coil. The basic control sequence is shown in Fig. 3. As space temperature falls below the heating setpoint, the heating output is increased. As space temperature increases above the cooling setpoint, the cooling output is modulated to 100%. Switching levels for staged heating/cooling and fan speeds are configurable. The fan may still be configured to run continuously during the zero energy band in the "occupied" mode. Additional configurable fan control features include fan minimum ON/OFF times, run-up, and overrun-times.

Excel 10 FCU Controllers use a PID control algorithm in which each of the three parameters can be configured. There are additional configurable boost parameters ("PID Boost:" "Cooling" and "Heating") which specify a range outside of which the heating or cooling outputs are turned ON fully for faster response (in the case of thermal actuators, this specifies the control hysteresis). The controllers are delivered with factory defaults for each of the parameters.

3	EN2B-0285GE51 R0909

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Contents Excel Appendix C LON Interface Revision History Appendix a Using An LNS tool to Commission a Fan Coil Unit Appendix B Configuring for Master/Slave Operation Typical system overview Description of DevicesOrganization of Manual Products CoveredApplicable Literature Product NamesControl Provided Control ApplicationSetpoint Knob SetpointsSetpoint Limits Setpoint from NetworkZEB Bypass Energy-Saving FeaturesOccupancy Status Operating Modes Safety FeaturesExcel 10 W7752 FCU Controllers ConstructionExcel 10 W7754 FCU Controllers Electrical Shock Hazard180 Controller Performance Specifications Fan Type ConfigurationsGeneral Type of Heating and Cooling Equipment Digital Input Reheat OutputExcel 10 Wall Module Options Common Temperature Control Master/Slave ControllersAbbreviations and Definitions Plan the System OverviewDetermine Other Bus Devices Required Step No DescriptionLonworks Layout Lay Out Communications and Power WiringGeneral Considerations Prepare Wiring DiagramsPower Wiring Power WiringVendor wire type PlenumLOW 230 XAL-Term ONW Orks TerminationExcel 10 Wall Modules Order EquipmentExcel 10 Sensors Echelon-Based Components and PartsUsing Plug-Ins Configure ControllersOutput Input Fan Equipment ControlMiscellaneous Switching LevelsZone Options Troubleshooting Excel 10 FCU Controllers and Wall Modules TroubleshootingAlarms CommissioningReturntonormal FCU AlarmsManual Mode Broadcasting the Service MessageProcedure Temperature Sensor CalibrationInput Configuration Options Output Configuration OptionsZone Control Options Network Variable BindingAppendix C LON Interface Page NV name Continuous Automode To 100% For the reheat output EN2B-0285GE51 R0909 Byte Ntcnonlinearize NoswitchNtcnonlinearized Byte FivepositionDiwindowclosed Byte DinotusedDioccupiedsensor DiairflowOnestage Byte FloatingTwostage ThreestageRelnotused Byte ReheatFreeuse Twopipe FourpipeUword Absolutemiddle OffsetBypassunoccupie NobuttonTable C3. Input Variables for Excel 10 FCU Controllers Modedisable Modeenable UnsuppressalarmsSuppressalarms OcnulInvalid Rqnormal Rqupdatestatus Rqupdatealarm RqreportmaskOFF NUL OFF1OFF2 Byte NormalhcmodeON1OFF2 OFF1ON2Ledoff Ledon Byte NormalfanmodeOpen NowindowClosed Table C4. Output Variables for Excel 10 FCU Controllers Alarmnotifydisabled RtncomfailtempresetRtncomfailsetptoffs RtncomfailschedoccOcbypass Ocstandby Almcomfailmanheat Almcomfailmancool AlmhwswmismatchOFF Notassigned Fieldeffectocc OFF Nofanspeedsw UbyteFieldhwoverride FieldschedoccCtldisabled CtlfanswitchoffOcunoccupied Ocbypass Ocstandby Ocunoccupied Ocbypass Ocstandby OcnulFanoffafteroncmd Not Actice ActiveFanruns ExternalnotacticeInvalid Uword StoffSton Notpressed OFF NoreheatPressed Contactopen Contactclosed UwordInvalid Byte Initial Stlow Stmed SthighDisabled EnabledNoalarm InalarmOpen Nowindow Alarm Suppressalarms AlarmnotifydisabledBugver Nodetype Word Table C5. Unused Variables for Excel 10 FCU ControllersAutomation and Control Solutions