Fisher 244EH, 244ER manual Thermocouple or Millivolt Inputs

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Thermocouple or Millivolt Inputs

• Pt100 2-wire RTD:

Lead Wire Resistance

Basic Error = ----------------------------------------------------------

Pt × Ro)

Cu ) × ( ΔTamb) × (Lead Wire Resistance) Error due to amb. temp. variation = ----------------------------------------------------------------------------------------------------------------

Pt) × (Ro)

Lead wire resistance seen by the transmitter = 150 m × 2 wires × 0.025 Ω/m = 7.5 Ω

Basic error =

7

.5 Ω

= 19.5 °C

(---0.00385------------------------Ω-------/---

Ω-------°---C-----)----×----(---100------------Ω-----)

Error due to amb. temp. var. of ± 25 °C

(0.0039 Ω / Ω °C) × (25 °C) × (7.5 Ω) ± °

=-------------------------------------------------------------------------------------------------------= 1.9 C

(0.00385 Ω / Ω °C) × (100 Ω)

Thermocouple or Millivolt Inputs

For integral mounting applications, the thermocouple can be connected directly to the transmitter. If mounting the transmitter remotely from the sensor, use appropriate thermocouple extension wire. Make connections for millivolt inputs with copper wire. Use shielding for long runs of wire.

Figure 2-12. Sensor Wiring Diagrams

 

Model 244E Sensor Connections

 

 

1 2 3 4

1 2

3

4

1 2

3 4

1 2 3 4

1 2 3 4

0000B01A-

2-wire

 

 

*

 

**

4-wire

T/C

3-wire

RTD with

644

RTD

RTD

 

Comp.

RTD

and mV

and V

and V

Loop

and V

 

 

*Rosemount Inc. provides 4-wire sensors for all single element RTDs. You can use these RTDs in 3-wire configurations by leaving the unneeded leads disconnected and insulated with electrical tape.

**The transmitters must be configured for a 3-wire RTD in order to recognize an RTD with a compensation loop.

2-15

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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 ApprovalsSection SAFETY MESSAGES1 Introduction MANUAL OVERVIEW General CONSIDERATIONSMechanical ElectricalPage SAFETY MESSAGES Warnings 2 InstallationThe tools needed for installation are as follows TOOLS NEEDED FOR INSTALLATIONFigure 2-1. Transmitter Installation Flowchart Example MOUNTINGMounting a Model 244EH to a DIN Rail Special Mounting ConsiderationsTransmitter INSTALLATION PROCEDURESHead 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 SensorMultichannel Installations Configuration SoftwareSystem Requirements Procedure for Windows 3.1 or Windows for Workgroups Choose the procedure that matches the operating system you are usingProcedure for Windows 95 or Windows NT Setting Up the Model 244EC Configuration Interface 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 CONFIGURATIONFigure 3-1. Models 244EH and 244ER Configuration Software Main Configuring a Single TransmitterConfiguration Window Configuring Several Transmitters Identically INTERMITTENT SENSOR ALGORITHM Viewing the Process VariableFigure 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 aboveTransmitter Behavior with Intermittent Sensor Detect ON ImplementationTransmitter Behavior with Intermittent Sensor Detect OFF Page SAFETY INFORMATION 4 Maintenance and TroubleshootingTROUBLESHOOTING 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 INSTALLATIONSFactory Mutual FM Approvals LOCATIONS CERTIFICATIONSCanadian Standards Association CSA Approvals KEMA Approvals Standard Australia Quality Assurance Service SAASpecial 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