iTherm Moduline TM121

Summary

Product identification

The iTHERM ModuLine TM121 is a metric version thermometer designed for standard applications with replaceable inserts.

Operating limits

• Measuring range: –50 to +650 °C (–58 to +2 012 °F)
• Pressure range: up to 50 bar (725 psi)
• Degree of protection: up to IP 68

Feed water

Process temperature range

• Max. –200 to +650 °C (–328 to +1 202 °F), depending on sensor type and material.

Process pressure range

• Pmax. = 50 bar (725 psi). The maximum possible process pressure depends on design, process connection, and process temperature.

Product water

Measuring principle

The device can utilize either Resistance Thermometers (RTD) or Thermocouples (TC):

• RTD: Based on Pt100 sensors (IEC 60751) with a resistance of 100 Ω at 0 °C. Available types include wire-wound (WW) and thin-film (TF).
  • WW sensors: Suitable for temperatures up to 600 °C (1 112 °F), but sensitive to vibrations.
  • TF sensors: Smaller and more vibration-resistant, with tighter tolerance limits (Class A) up to approximately 300 °C (572 °F).
• TC: Utilize the Seebeck effect to measure temperature differences. Standardized types include J, K, and N, following IEC 60584 and ASTM E230/ANSI MC96.1 standards.

Measuring range

The measuring range depends on the sensor type:

• Pt100 (TF) Basic: –50 to +200 °C (–58 to +392 °F)
• Pt100 (TF) Standard: –50 to +400 °C (–58 to +752 °F)
• Pt100 (TF) iTHERM StrongSens (≤ 60g vibration): –50 to +500 °C (–58 to +932 °F)
• Pt100 (WW) Extended: –200 to +600 °C (–328 to +1 112 °F)
• Thermocouple TC, type J: –40 to +750 °C (–40 to +1 382 °F)
• Thermocouple TC, type K: –40 to +1 100 °C (–40 to +2 012 °F)
• Thermocouple TC, type N: Not specified in the extract.

Performance characteristics

• Maximum measurement error (RTD assembly):
  • Class A: ± (0.15 + 0.002 · |t| °C)
  • Class AA: ± (0.1 + 0.0017 · |t| °C)
  • Class B: ± (0.3 + 0.005 · |t| °C)
• Response time (t90 in water, 0.4 m/s, 10 K step):
  • 9 mm thermowell diameter: RTD insert 90 s, TC insert 60 s
  • 11 mm thermowell diameter: RTD insert 100 s, TC insert 90 s

Electrical

Output signal

• Analog output 4 to 20 mA, HART® protocol
• IO-Link®

Power supply

• For transmitters: 18 to 30 VDC is mentioned for the TMT36 transmitter.

Insulation resistance

• RTD: > 100 MΩ at 25 °C (between terminals and sheath material, 100 V DC test voltage).
• TC: > 1 GΩ at 20 °C and > 5 MΩ at 500 °C (between terminals and sheath material, 500 V DC test voltage).

Mechanical / hydraulic

Thermowell

• Diameter: ⌀9 mm (0.35 in) or ⌀11 mm (0.43 in)

Inserts

• Diameter: ⌀6 mm (0.24 in)
• RTD: Thin-film (TF) sensors available.
• Thermocouple: Type K available for measuring ranges up to 650 °C (1 202 °F).

Materials

• AISI 316L/1.4404, 1.4435: Recommended max. temperature for continuous use in air: 650 °C (1 202 °F). Good corrosion resistance.
• Alloy 600/2.4816: Recommended max. temperature for continuous use in air: 1 100 °C (2 012 °F). Good resistance to aggressive atmospheres.

Process connections

• Threaded: M, NPT, or G threads (e.g., M20x1.5, NPT ½"). Max. static process pressure for threaded connections: 400 bar (5 802 psi) at +400 °C (+752 °F).
• Compression fittings: Available in materials like 316L. Max. pressure: 40 bar (580 psi) at +200 °C (+392 °F) or 25 bar (363 psi) at +400 °C (+752 °F).
• Flanges: Available according to DIN, EN, ASME, JIS, and HG/T standards.

Weight

• 1 to 10 kg (2 to 22 lbs) for standard versions.

Ambient conditions

• Terminal head ambient temperature:
  • With mounted head transmitter: –40 to +85 °C (–40 to +185 °F)
  • With mounted head transmitter and display: –20 to +70 °C (–4 to +158 °F)
• Humidity: Max. 95% relative humidity (as per IEC 60068-2-30). Condensation permitted.

Shock and vibration resistance

• Inserts exceed IEC 60751 requirements. Vibration resistance varies by sensor type, with iTHERM StrongSens and QuickSens TF up to 600 m/s² (60g).

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

Official datasheet (PDF)

Lenntech datasheet mirror