PR-21SL-M12

Supported Applications

The Omega PR-21SL Series consists of spring-loaded RTD (Resistance Temperature Detector) sensors designed for use in thermowells. These probes feature M12 A-Coded Male Connectors and are engineered to fit all standard 0.260" bore thermowells, which are sold separately.

Operating Conditions & Performance

The series operates within a temperature range of -50 to 260°C (-58 to 500°F), with a maximum connector temperature limit of 85°C (185°F). The sensors utilize Pt100 elements and meet Class A accuracy per IEC 60751, defined as ±(0.15 + 0.002*t)°C where "t" = temperature in °C regardless of sign. At 0°C, the resistance is specified at 100.00 Ω with a tolerance of ±0.06Ω for Class A models.

Wetted materials consist of 0.89 (0.035) diameter music wire conforming to ASTM A228. The series is RoHS compliant.

Configuration Options

The PR-21SL Series offers configurable stem lengths and wiring arrangements to accommodate specific thermowell dimensions and instrumentation requirements.

• Stem Lengths: Standard catalog models are available in 2½", 4", 6", 9", 12", 15", 18", and 24" lengths. Custom probe lengths up to 24" can be ordered by modifying the stem length code (e.g., "1250" for 12½").
• Wiring Configurations: Sensors are available in 2-Wire, 3-Wire, and 4-Wire arrangements. The model number suffix indicates wiring: change the final digit from “-1” to “-2” for alternate wiring.
• Electrical Connection: Integral M12 A-Coded Male Connectors are standard on all units.

The adjustable self-gripping spring mechanism allows these probes to be used in shorter length thermowells. Probe length equals the thermowell stem length for proper fitment.

Available Options and Accessories

• SPRTX-SS In-Line Transmitter
• TX94A-SS Transmitter
• UWRD-2-S Wireless Transmitter
• M12C Extension Cables
• M12 Extension Cables
• 4 to 20 mA Transmitters

Key Product Differences

Variants within the series are distinguished by stem length and wiring configuration. The model number structure follows the pattern PR-21SL-3-R-A-L-M12-X, where R denotes resistance (e.g., 100 for Pt100, 1000 for Pt1000), L represents the stem length in millimeters or inches as coded (e.g., "0400" for 4", "0600" for 6"), and X indicates the wiring arrangement (-1 or -2).

The series includes both Pt100 models (resistance at 0°C: 100.00 Ω) and Pt1000 models (e.g., PR-21SL-3-1000-A variants), though the primary specification table details Class A performance for the 100 Ω elements.