Fisher 244EH, 244ER manual Intermittent Sensor Algorithm and Damping

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Intermittent Sensor Algorithm and Damping

Intermittent Sensor Algorithm and Damping

Step Changes Greater than Threshold Value

Input

 

Output without Algorithm

Total of All Step Changes

Output with Algorithm (Default)

0500 1000 1500 2000 2500 3000 3500 4000

Time (in 500 ms increments)

D)If an open sensor is validated at the end of the first update cycle (Time = 500 ms), the output will go directly to alarm level. The original spike (at Time = 0 ms) will not be seen at the output.

Open Sensor

 

 

Input

 

 

 

 

 

 

False Output

 

 

 

 

 

Output without Algorithm

 

 

 

Alarm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Output with Algorithm (Default)

0500 1000 1500 2000 2500 3000 3500 4000 Time (in 500 ms increments)

Case 3: Temperature Change Within the

Threshold Value (2 % of Range)

If the transmitter detects an input change that is within the threshold value, it reports the new value within one output cycle (500 ms).

If the transmitter has both intermittent sensor detect and damping enabled, the output reading is calculated by the following formula:

Damped Value = (P N) × 2T U+ N

-----------------

2T + U

P = previous damped value

N = new sensor value

T = damping time constant

U = update rate

The transmitter outputs the corresponding value on the damping curve within 1.75 to 2.0 seconds and updates the output reading every 500 ms thereafter, according to the damping equation above. At the value to which the damping time constant is set, the transmitter output is at 63% of the input change.

3-7

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Contents Models 244EH and 244ER PC-Programmable Temperature Transmitters 00809-0100-4737 English Rev. EAPage Models 244EH and 244ER PC-Programmable Temperature Transmitters Product Manual¢00809-0100-4737f¤ 00809-0100-4737 Rev EA 10/00Page Installation Table of ContentsMaintenance and TroubleshootingReference Data APPENDIX AAPPENDIX B ApprovalsSAFETY MESSAGES Section1 Introduction MANUAL OVERVIEW General CONSIDERATIONSMechanical ElectricalPage SAFETY MESSAGES Warnings 2 InstallationTOOLS NEEDED FOR INSTALLATION The tools needed for installation are as followsFigure 2-1. Transmitter Installation Flowchart Example MOUNTINGMounting a Model 244EH to a DIN Rail Special Mounting ConsiderationsINSTALLATION PROCEDURES TransmitterHead Mount Transmitter with DIN Plate Style Sensor Using Threaded Style Sensor Figure 2-6. Typical Model 244EH Transmitter Mounting Configurationand Assembly Head Mount Transmitter with Threaded SensorUsing Integral Mount Sensor and Assembly Figure 2-7. Typical Rail Mount Transmitter Mounting ConfigurationTo complete the assembly, follow the procedure described below 6. Run sensor lead wires from the sensor assembly to the transmitter644-0000A04B Rail Mount Transmitter with Threaded SensorConfiguration Software Multichannel InstallationsSystem Requirements Choose the procedure that matches the operating system you are using Procedure for Windows 3.1 or Windows for WorkgroupsProcedure for Windows 95 or Windows NT Model 244EC Configuration Interface Setting Up the Model 244EC Configuration InterfaceScreen Conventions Figure 2-10. Complete Transmitter Configuration System FIELD WIRINGRTD or Ohm Inputs Sensor ConnectionsExamples of Approximate Lead Wire Resistance Effect Calculations Sensor Lead Wire Resistance Effect RTD InputGiven Total cable length = 150 mThermocouple or Millivolt Inputs Figure 2-13. Transmitter Power, Sensor, and Configuration Terminals FAILURE MODE Changing Switch Positions3 Operation POWER SUPPLY Surges/TransientsGrounding CONFIGURATIONConfiguring a Single Transmitter Figure 3-1. Models 244EH and 244ER Configuration Software MainConfiguration Window Configuring Several Transmitters Identically Viewing the Process Variable INTERMITTENT SENSOR ALGORITHMFigure 3-2. Viewing the Process Variable with the 244EC Case 1 Open Sensor Case ExamplesCase 2 Temperature Change Greater than the Threshold Value2% of Output RangeCase 3 Temperature Change Within the Threshold Value 2 % of Range Intermittent Sensor Algorithm and Damping2.0 seconds, the transmitter outputs the reading that corresponds to Intermittent Sensor Detect Advanced Featurethe damping curve at that time , and continues to calculate and continues to approach the input curveaccordingto theequation aboveImplementation Transmitter Behavior with Intermittent Sensor Detect ONTransmitter Behavior with Intermittent Sensor Detect OFF Page 4 Maintenance and Troubleshooting SAFETY INFORMATIONTROUBLESHOOTING Model 244EH software version Error Message Troubleshooting ChartCause and Possible Solutions TABLE 4-1. Models 244EH and 244ERAppendix TRANSMITTER SPECIFICATION FunctionalA Reference Data Power SupplyUpdate Time PerformancePower Supply Effect CE Electromagnetic Compatibility Compliance TestingTABLE A-2. Model 244E Input Options and Accuracy AccuracySensor InputAmbient Temperature Effect Transmitters can be installed in locations where the ambientWeight PhysicalElectrical Connections Materials of ConstructionModel ORDERING INFORMATIONProduct Description HeadTABLE A-6. Transmitter Accessories TABLE A-5. Model 244EC Configuration Interface Ordering InformationTypical Model Number 244EC Part DescriptionCustom Configuration Standard ConfigurationUnless specified, transmitter will be shipped as follows TaggingEnclosure and Model 244EC Configuration Interface DIMENSIONAL DRAWINGS TransmitterConfiguration Interface Model 244ERPage B Approvals HAZARDOUS LOCATIONS INSTALLATIONSLOCATIONS CERTIFICATIONS Factory Mutual FM ApprovalsCanadian Standards Association CSA Approvals Standard Australia Quality Assurance Service SAA KEMA ApprovalsSpecial Conditions for Safe Use Gostandart INSTALLATION DRAWINGSInstallation Drawing Rev. AB Figure B-1. Canadian Standards Association CSA Intrinsic SafetyFigure B-2. Canadian Standards Association CSA Explosion-Proof Installation Drawing Rev. AA00644-0009, Rev. AA Figure B-3. Factory Mutual FM Intrinsic Safety Installation Drawing00644-1049, Rev. AB Figure B-4. Factory Mutual FM Explosion-Proof Installation DrawingC Models 644 and 244E Temperature Transmitters Manual Supplement OLD TRANSMITTER Transmitter Design Sensor Wiring Diagrams Special MountingConsiderations Models 644H and 244EHConsiderations HART Communicator Model 644H only NEW TRANSMITTER2. Select 1 Off-line, 1 New Configuration, Rosemount, 644 Temp Use with an Existing DIN Plate Style SensorBASEFFA1 Intrinsically Safe Installation Entity Parameters SPECIFICATIONSFactory Mutual3 Entity ParametersIndex Wiring Page Product documentation available at