iTemp TMT31

Summary

Product identification

• Product: iTEMP TMT31 Temperature transmitter
• Type: Form B (flat face) head transmitter with 4 to 20 mA analog output.
• Document: TI01613T/09/EN/01.21

Application

The iTEMP TMT31 is characterized by its reliability, long-term stability, high precision, and diagnostic functions. It is designed for maximum safety and availability and is intended for installation in a terminal head B.

Benefits

• Diagnostics information according to NAMUR NE107.
• Rapid, no-tools wiring due to optional spring terminal technology.
• Increased safety with Ex approvals.
• High accuracy and flexibility with Callendar-van-Dusen equation.

Measuring System

• Input Type: 1 x RTD (Resistance Temperature Detector)
• Configuration: 2-wire device with one measuring input and one analog output. Installable in a Form B (flat face) terminal head as per DIN EN 50446.

Diagnostics

Standard diagnostic functions include:

• Cable open-circuit, short-circuit of sensor wires
• Incorrect wiring
• Internal device errors
• Overrange and underrange detection
• Device temperature overrange/underrange detection
• Low voltage detection

Input

• Measured Variable: Temperature (temperature-linear transmission behavior)

Measuring Range

• Pt100 (Callendar van Dusen): Measuring range limits are specified by entering limit values dependent on coefficients A to C and R₀.
• Connection Type: 2-wire, 3-wire, or 4-wire connection.
• Sensor Current: ≤ 0.3 mA.
• Wire Resistance Compensation:
  • 2-wire circuit: Possible (0 to 30 Ω).
  • 3-wire and 4-wire connection: Up to max. 50 Ω per wire.

Output

• Output Signal: 4 to 20 mA, 20 to 4 mA (inversely configurable).
• Failure Information: As per NAMUR NE43.
  • Underranging: Linear drop from 4.0 to 3.8 mA.
  • Overranging: Linear increase from 20.0 to 20.5 mA.
  • Failure (e.g., sensor failure, short-circuit): ≤ 3.6 mA ("Low") or ≥ 21 mA ("High"), selectable.
• Linearization/Transmission Behavior: Temperature-linear.
• Filter: 1st order digital filter (0 to 120 s), Network frequency filter (50/60 Hz, not adjustable).
• Switch-on Delay: ≤ 5 s. During switch-on delay, output current is ≤ 3.8 mA.

Power Supply

• Supply Voltage: 10 V ≤ Vcc ≤ 36 V (standard, protected against polarity reversal). Values for hazardous areas are in Ex documentation.
• Current Consumption: 3.5 to 22.5 mA.

Electrical Connection

• Terminals: Choice of screw or push-in terminals for sensor and power supply cables.

Wire end ferrules are required for spring terminals and flexible cables ≤ 0.3 mm².

Performance Characteristics

• Response Time: ≤ 0.5 s.
• Reference Operating Conditions: Calibration temperature +25 °C ±3 K, Supply voltage 24 V DC, 4-wire circuit for resistance adjustment.

Maximum Measured Error

Errors are specified as ±2 s (Gaussian distribution) and include non-linearities and repeatability.

¹⁾ whichever is higher.

Operating Influences

(Errors as ±2 s, Gaussian distribution)

• Long-term drift (±)¹⁾:
  • After 1 year: 0.05 K or 0.03 % of span
  • After 3 years: 0.06 K or 0.04 % of span
  • After 5 years: 0.07 K or 0.05 % of span ¹⁾ whichever is higher.

Sensor Adjustment

• Sensor-transmitter-matching: Utilizes Callendar-Van-Dusen coefficients to improve accuracy.
• 1-point adjustment (offset): Shifts the sensor value.
• Current output adjustment: Correction of 4 and/or 20 mA output values.

Mounting

• Mounting Location:
  • Terminal head Form B (flat face) as per DIN EN 50446.
  • With DIN rail clip on DIN rail as per IEC 60715 (TH35).

Environment

• Ambient Temperature: –40 to +85 °C (–40 to +185 °F).
• Storage Temperature: –50 to +100 °C (–58 to +212 °F).
• Operating Altitude: Up to 4000 m above sea level.
• Humidity: Max. 95 % relative humidity (as per IEC 60751:2008), condensation permitted.
• Climate Class: C1 according to IEC 60654-1.
• Degree of Protection: IP 00 (screw terminals), IP 30 (spring terminals). Dependent on installed terminal head/housing.
• Shock and Vibration Resistance: Vibration as per DNVGL-CG-0339 : 2015 and DIN EN 60068-2-27 (8.6 to 150 Hz at 3g). Shock as per KTA 3505.
• Electromagnetic Compatibility (EMC): CE conformity. Interference immunity as per IEC/EN 61326 series, industrial requirements. Interference emission as per IEC/EN 61326 series (CISPR 11), Class B, group 1.

Measuring Category

• Measuring category II as per IEC 61010-1.

Pollution Degree

• Pollution degree 2 as per IEC 61010-1.

Mechanical Construction

• Weight: 40 to 50 g.
• Materials: All materials are RoHS-compliant.
  • Housing: Polycarbonate (PC).
  • Terminals: Nickel-plated brass (screw), Tin-plated brass (push-in), contact springs 1.4310, 301 (AISI).
  • Potting Compound: SIL gel.

Operability

• Remote Operation: Device parameters are configured via the CDI interface using specialized configuration tools.
• Write Protection: Software write protection using a password.

Certificates and Approvals

Current certificates and approvals are available via the Endress+Hauser Product Configurator online.

MTTF

• Mean Time To Failure (MTTF): 418 years.

Ordering Information

Detailed ordering information is available via Endress+Hauser sales organizations or the Product Configurator online.

Accessories

Various accessories are available, including:

• Device-specific: Adapter for DIN rail mounting, DIN rail clip, DIN mounting set, US M4 securing screws.
• Communication-specific: Commubox FXA291, Configuration kit TXU10.
• Service-specific: Applicator software, Configurator tool, DeviceCare SFE100, FieldCare SFE500.
• System components: RN22/RN42 active barriers, RIA15 process display, RNB22 system power supply.

Documentation

• Operating Instructions
• Description of Device Parameters
• Supplementary ATEX and CSA documentation

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Disclaimer: This extraction may miss figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

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