Enviro EA800 owner manual Power Supply / Sensor Voltage Selection

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Power Supply / Sensor Voltage Selection

Sensors

Power Supply / Sensor Voltage Selection

In order to determine the power supply voltage necessary to ensure correct full-scale operation, it is necessary to identify all voltage drops within the current loop.

Figures 6 and 7 show an EA800 drop of 4.0 VDC. This value accounts for the voltage drop generated by connecting the 4-20mA sensor to the EA800 using 1000 feet of 22 AWG wire.

Now it is only necessary to identify the operating voltage range of the 4-20mA sensor, more importantly the minimum operating voltage. Once identified, the minimum operating voltage of the sensor can be added to the 4.0V voltage drop of the EA800 (+ wire) to determine the power supply voltage necessary to ensure correct full-scale operation.

Example:

■Assume that a 4-20mA sensor whose operating input voltage range is 10 – 30V has been selected for use. Therefore the minimum operating voltage of the sensor is 10V (Vsensor). When the 4.0V drop of the EA800 (and wire) is added, it can be determined that at least 14VDC is needed to power the loop.

■If the EA800 is connected to a 12VDC power supply, use of the sensor in this example requires an external power supply of at least 14V as shown in Figure 7.

It is important to not exceed the maximum operating voltage of the 4-20mA sensor, as specified within the sensor’s product specification.

The following formula provides the basis for the selection matrix shown in Table 7. Please use Table 7 to select either the proper sensor rating to be used with a known power supply, or select a power supply for a known sensor rating.

RL < (Vcc – x) .023 where:

■RL = Loop resistance of 200

■Vcc = Power supplied to EA800 or Aux Power Out

■X = Sensor voltage (max)

Table 7 4-20mA Voltage Select Matrix

Power Supplied to EA800	Vsensor (max.) [Maximum		Power Supplied to EA800 or	Vsensor (max.) [Maximum
or AUX. Power Out	sensor voltage rating]		AUX. Power Out	sensor voltage rating]

11 VDC	7 VDC		19 VDC	15 VDC

12 VDC	8 VDC		20 VDC	16 VDC

13 VDC	9 VDC		21 VDC	17 VDC

14 VDC	10 VDC		22 VDC	18 VDC

15 VDC	11 VDC		23 VDC	19 VDC

16 VDC	12 VDC		24 VDC	20 VDC

17 VDC	13 VDC		25 VDC	21 VDC

18 VDC	14 VDC		26 VDC	22 VDC

12	D-011-0152

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Contents D-011-0152 Limitations of the Alarm System or Device Table of Contents InstallationGeneral Information PreparationOperation General Information OverviewHow to Use This Manual General Information Block DiagramsD-011-0152 Symbols on the Product or Manual Labeling General Information Monitoring ScreensD-011-0152 Keys Base Unit Connections Access Control and Passwords will sound when an alarm occurs if DISABLE is System Configuration Parametersselected Sensors Temperature Sensors4-20mASensors Humidity SensorsTheory of Operation Power Supply / Sensor Voltage Selection Multi-FunctionSensors Water SensorsContact Closure Sensors Sensor Parameter Descriptions ResolutionMaximum Allowed High Scaled ValueRelay Operation Relay Operation D-011-0152Preparation D-011-0152 From 11-26VDC power supply To alarm-on-closedloop circuit power supplied via loop From 11-26VDC power supplyD-011-0152 Installation Power RequirementsTools and Supplies Required Mounting the EA800 Rear PlateEA800 Base Unit Power Connections Install the Wired SensorsInstall the Wireless Sensors RESET BUTTON SENSOR MODEL NORESET BUTTON SENSOR MODEL NOD-011-0152 J6 Input 1 Input 2 Input 3 InputConnecting Wired HA-III+Humidity Sensors Connecting Wired 4-20mASensors Connecting the EA800 Alarm Outputs ProgrammingAccessing the MAIN MENU for Programming Configuring System Parameter Settings3.Enter the SYSTEM menu and then select the CONFIGURATION menu as shown below DISABLED is selected Setting the Current Date Setting the Time D-011-0152Adding Wireless Sensors Adding a Wireless Temperature SensorAdding Wireless Sensors D-011-0152Installation D-011-0152D-011-0152 Installation Adding a Wireless Humidity SensorD-011-0152 D-011-0152 Installation D-011-0152D-011-0152 Select N.O. Contact or N.C. Contact InstallationD-011-0152 Verify Wireless Signal Strength D-011-0152Adding Wired Sensors Adding a Wired Temperature SensorAdding Wired Sensors Adding a Wired HA-III+Humidity SensorD-011-0152 Adding a Wired WaterBug Sensor Note A supervised WaterBug sensor must be usedSelect N.O. Contact or N.C. Contact Adding a Wired Contact Closure SensorD-011-0152 Adding a 4-20mASensor Configuring the Relays Operation Monitoring Environmental ConditionsViewing Sensor Settings Viewing Active AlarmsViewing the Alarm Log Viewing Pending Alarm InformationViewing Limit Settings Viewing the Event LogViewing the Sensor Log Viewing Firmware InformationOperation D-011-0152Viewing RF Information Viewing RF InformationMaintenance Locking and Unlocking the EA800Pausing Monitoring and Cancelling Pause Adding a Sensor Replacing a SensorEditing Sensor Parameters SENSORS screenDeleting a Sensor Reprogramming a RelayF3 F3 Changing the Date Format Changing the Time FormatChanging the Date or Time Setting Changing Sensor Data Collection FrequencyChanging the Buzzer Setting Changing the Buzzer SettingMaintenance Changing the PasswordD-011-0152 Clearing the Sensor Log Clearing the Alarm LogClearing the Alarm Log Maintenance Updating the FirmwareD-011-0152 Saving Configuration Settings F3 LOAD/SAVE CONFIG screenLoading Configuration Settings CONFIG screenExported Alarm Data Exporting the Stored LogsExported Event Data Exported Sensor Data12/24/2007 07 06 03 PM Sensor deletedExporting the Stored Logs D-011-0152Troubleshooting ACTIVE ALARMS screenVerifying RF Signal Strength Viewing Signal Strength for a Wireless SensorSpecifications Base Unit and Sensor SpecificationsAccessories Appendix A Screen Maps Figure 17. Locked Screen MapFigure 18. Unlocked Screen Map - Top Level D-011-0152Figure 19. Sensors Screen Map Appendix A Screen MapsD-011-0152 Figure 20. Add New Sensor Screen Map D-011-0152Appendix A Screen Maps Figure 21. Edit Sensor Screen MapFigure 22. Relay Screen Map D-011-0152Figure 23. Data Log Screen Map D-011-0152Figure 24. System Screen Map Appendix A Screen MapsD-011-0152 Figure 25. Configuration Screen Map D-011-0152Appendix B Planning Worksheet InstallationAlarm Condition Appendix B Planning WorksheetD-011-0152 C Wiring Diagram AppendixD-011-0152 Appendix D System Configuration Record Unit of Measure Appendix D System Configuration Record Sensor 6 Settings wireless Appendix D System Configuration Record D-011-0152 Warranty and Service Information Manufactured in the U.S.A by Winland Electronics1950 Excel Drive, Mankato, MN, Outside MN Phone Phone Fax