Honeywell W7761A Window Sensor StatusWndw, Dirty Filter Monitor, Series 60 Modulating Control

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EXCEL 10 W7761A INPUT/OUTPUT DEVICE

The T7770A,B,C,D wall module is the room space temperature sensor—(current feature that can be used with the RIO Device). When it is configured, it provides the temperature input that can be shared with the W7750 or W7751 controllers. If there are multiple space sensors in a area controlled by one W7750 CVAHU, then the space temperatures can be wired into the W7761A controller and mapped to the Zone Manager. The Zone Manager can average all of the space temperatures and then have that value can be bound to the W7750 controlling that area.

Window Sensor (StatusWndw)

The digital input for a window contact can be wired into the W7761A device and then bound to a W7750 CVAHU to disable its temperature control algorithm if someone has opened a window or door in the room or area that the W7750 is serving. When a window is detected to be Open (digital input contacts Open equals window open), the normal temperature control is disabled, and the W7750 Controller enters the Freeze Protect mode. Freeze Protect mode sets the space setpoint to 50 °F (10°C) and brings on the fan and heat if the space temperature falls below this setpoint. Normal temperature control resumes on window closure.

Dirty Filter Monitor

The air filter in the air handler can be monitored by a digital input in the W7761A and an alarm issued by the Zone Manager when the filter media needs replacement. The two methods of monitoring the filter are:

1.A differential pressure switch whose contacts are connected to a digital input on the W7761A and;

2.A 2 to 10V differential pressure sensor wired to a voltage input on the W7761A. If the analog input sensor is used, its measured value 0 to 5 inw (0 to 1.25 kPa) is compared to a user-selectable setpoint in the Zone Manager, the comparison is done in the Zone Manager - valid range: 0 to 5 inw (0 to 1.25 kPa), and the Dirty Filter alarm is issued by the Zone Manager when the pressure drop across the filter exceeds the setpoint.

Series 60 Modulating Control

Series 60 Control is also commonly referred to as Floating Control. The Excel 10 W7761A Device can drive Series 60 type actuators to control a modulating damper or valve actuator. The W7761A device contains no control software, so these outputs would have to be bound to either the Zone Manager or other Excel 10 controllers. When floating control is used, the full-stroke motor drive time of the actuator must be entered into the configuration parameter DO1FlSpeed (for output 1), DO2FlSpeed (for output 2). When Floating control is configured, two digital outputs are required, so the user has to change the configuration parameter for the appropriate digital outputs.

Pulse Width Modulating (PWM) Control

The Excel 10 W7761A device can drive a PWM-type actuator to control a modulating actuator. The W7761A device contains no control software, so these outputs would have to be bound to either the Zone Manager or other Excel 10 controllers. PWM control positions the actuator based on the length, in seconds, of the pulse from the digital output. The controller outputs a pulse whose length consists of two parts, a minimum and a maximum. The minimum pulse time represents the analog value of zero percent (also indicates a signal presence) and the maximum pulse length that represents an analog value of 100 percent. If the analog value is greater than zero percent, an additional time is added to the minimum pulse time. The length of time added is directly proportional to the magnitude of the analog value. If PWM control is used, the configuration parameters for the PWM operation must be specified. These parameters are DO1PWMPeriod and PWMZeroScale, and PWMFullScale.

Example: To find the pulse width of a valve actuator (for example stroke mid position - 50 percent) with the PWMZeroScale =

0.1seconds, PWMFullScale = 25.5 seconds, and the PWMPeriod = 25.6 seconds. There are 256 increments available, so the number of increments required for 50 percent would be (0.5 X 256) or 128. The time for each increment for this industry standard pulse time is 0.1 seconds. The pulse width is the minimum time (0.1 second) + the number of increments (128 times the seconds added 0.1) = 12.9 seconds. The W7750B Controller would command the valve output on for 12.9 seconds every

25.6seconds to maintain the valve position at 50 percent.

Indoor Air Quality (IAQ) Override

The Excel 10 W7761A Device can monitor an IAQ sensor and that input can be bound to a W7750 CVAHU Controller that supports an IAQ override feature, that upon detection of poor air quality in the space, allows the economizer dampers to be opened above the standard minimum position setting to a value set in EconIAQPos (parameter located in W7750). Two different methods of detecting poor air quality are supported, The first is by using an IAQ switch device connected to a digital input on the W7761A Device, where a contact closure indicates poor air quality. This digital input would then be bound to the W7750 Controller that is serving the area being monitored and would initiate the IAQ override mode. The second is through an analog input that connects to a CO2 Sensor (0 to 10V). The measured value of CO2 from this sensor (0 to 2000 ppm) is mapped into the Zone Manager where it is compared to a setpoint (parameter located in the Zone Manager). When the CO2 level is higher than the setpoint, the Zone Manager can initiate an IAQ alarm. A pseudo digital point in the Zone Manager can be bound to the W7750 CVAHU Controller which can initiate the IAQ override mode.

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Contents Excel 10 W7761A Remote Input/Output Device Appendices List of TablesTypical system overview Description of DevicesOrganization of Manual Control ApplicationControl Provided Products CoveredProduct Names Abbreviations and Definitions Agency ListingsExcel 10 W7761A INPUT/OUTPUT Device Controllers ConstructionExcel 10 W7761A Remote I/O Device W7761A construction in in. mm List Of Available Points W7761A Performance Specifications PowerMemory Capacity Specified Space Temperature Sensing RangeEnvironmental Operating Temperature Shipping TemperatureMixed Air Temperature Discharge Air TemperatureOutdoor Air Temperature Return Air Temperature5585 Wall ModulesT7780 construction, subbase dimensions in in. mm ConfigurationsWall Module Options Mixed-Output-Type ControlOccupancy Sensor Window Open/Closed Digital InputPlan The System OverviewApplication Steps Step No Description Determine Other Bus Devices Required Lay Out Communications and Power WiringBus Layout 750,1$ Power Budget Calculation Example Power WiringLine Loss VA Ratings For Transformer Sizing Device DescriptionNema class 2 transformer voltage output limits VA RatingLine VOLTAGE` GREATER` Than 150 VAC General Considerations Prepare Wiring DiagramsW7761A Devices Terminal Number Description W7761A I/O DescriptionTemperature Sensor DE V IC E Window Contact Contact Closed = Occupancy Sensor Occupied Valve Actuator Typical Pneumatic transducer Series 60 Floating to W7761A Bus Termination ModuleSee for E-Bus termination wiring options +$672 Sensors Order EquipmentExcel 10 W7750 Controllers T7770 Wall ModulesEchelon Based Components and Parts AccessoriesCabling Temperature Degrees Excel 10 Alarms Broadcasting the Service MessageW7761A Device Status LED LED States T7780 Ddwm Bypass PushbuttonAdding Analog Inputs Enthalpy 4 to 20 mA Appendix A. Using E-Vision to Commission a W7761 DeviceAdding Other VOLTAGE/CURRENT Sensors Adding Digital Inputs Appendix B. Sequences of Operation Room Temperature Sensor RmTempCommon Operations Pulse Width Modulating PWM Control Window Sensor StatusWndwDirty Filter Monitor Series 60 Modulating ControlCO 2 Concentration Temperature Relative HumidityRelative Air FlowTable C1. Input/Output Points Left DefaultTable C1. Input/Output Points Right Excel 10 W7761A INPUT/OUTPUT Device Values that can be assigned to any output channels English Metric or User Address DI3Sel1Type Refer to the description for DI1Sel1Type Stoff Stnul Stlow Stmed Sthigh Ston DO2Type Excel 10 W7761A INPUT/OUTPUT Device SrcDigIn2Sts Refer to the description for SrcDigIn1Sts Table C2. Control Parameters Left SH MA DA EV HW MN TS Table C2. Control Parameters RightTable C3. Status Points Left NoalarmTable C3. Status Points Right RIO1 Software version NvoStatus InOverride SH MA DA EV HW MN TS Table C4. Configuration Parameters Left Table C4. Configuration Parameters Right DO0 Higher than the value specified for AILowLimit DO4 Seconds = 25.6 seconds DO6PWMPeriod Refer to the description for DO1PWMPeriod Table C5. Direct Access And Special Points Right Table C5. Direct Access And Special Points LeftFig. D-1. Point capacity estimate for Zone Manager Approximate Memory Size Estimating ProcedureSensor Use Appendix E. Sensor Data for CalibrationResistance Sensors Sensor Type1956.79 Table E-4. Sensor Voltage Versus Humidity Voltage/Current SensorsHumidity Percentage Sensor Voltage C7600C1008 4 to 20 mA C7600C output current vs. humidity Sensor Type Fig. E-6. Graph of Sensor Current versus Enthalpy volts CO 2 Concentration PPM Sensor Voltage Table E-9. Sensor Voltage Versus CO 2 ConcentrationTable E-10. Sensor Voltage Versus Input Voltage To A/D Table E-11. Sensor Voltage Vdc Versus Pressure Inw Voltage to A/D Sensor VoltagePressure Inw kPa Sensor Voltage Vdc 3ODD
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