Thermoprobe TL1-R High-Precision Digital Laboratory Thermometer

Overview

The Thermoprobe TL1-R High-Precision Digital Laboratory Thermometer is a rigorously engineered contact temperature measurement instrument designed for demanding laboratory, quality control, and calibration applications where traceable accuracy and long-term stability are critical. Built around a 200 Ω wound-wire platinum resistance temperature detector (Pt RTD), the TL1-R adheres to fundamental principles of resistance thermometry—measuring minute changes in electrical resistance proportional to temperature—with full compliance to IEC 60751 Class A tolerances (equivalent to ±(0.15 + 0.002|t|) °C). Its sensor architecture ensures minimal stem conduction error and high thermal responsiveness, validated by a documented response time of ≤3 minutes to within ±0.1°C across a 0–50°C water bath—meeting ASTM E74–22 requirements for thermometer verification protocols. The device delivers NIST-traceable calibration with an uncertainty budget documented per ISO/IEC 17025–accredited procedures, making it suitable for GLP and GMP environments requiring auditable metrological integrity.

Key Features

• High-resolution 0.001°C display on a dedicated 0.25-inch LCD—optimized for legibility under controlled lab lighting and glove use
• True Class A Pt100-equivalent performance: ±0.04°C absolute accuracy over its full operating range (−18°C to +150°C)
• Rugged anodized aluminum housing (3.5″ × 12″) with silicone sealing—IP54-rated against dust and incidental moisture ingress
• Stainless-steel probe (20 cm length, 6.35 mm diameter) with 11 cm minimum immersion depth for compliant RTD measurements per ASTM E74 and ISO 17025
• Intelligent power management: auto-shutdown after 20 minutes of inactivity or continuous operation; 400-hour battery life at 21°C using a single CR2032 cell
• Full unit interchangeability: real-time toggle between °C and °F without recalibration or firmware reset
• Battery-low and sensor-fault diagnostics displayed directly on screen—no external software required for basic health monitoring

Sample Compatibility & Compliance

The TL1-R is intended for direct-contact measurement of liquids, semi-solids, and ambient air in controlled laboratory settings. Its stainless-steel probe is chemically inert to common solvents, aqueous buffers, oils, and food-grade matrices—validated for use in USP Analytical Instrument Qualification workflows. The instrument conforms to key regulatory frameworks: its NIST-traceable calibration report satisfies FDA 21 CFR Part 11 data integrity prerequisites when used as a standalone reference standard; its design meets IEC 61000-4 electromagnetic immunity standards for lab instrumentation; and its mechanical construction aligns with ISO 9001:2015 clause 7.1.5 for monitoring and measuring resource control. It is not rated for pressurized, explosive, or sterilizable environments (e.g., autoclaving).

Software & Data Management

The TL1-R operates as a self-contained, firmware-driven instrument with no embedded Bluetooth, USB, or serial interface. All measurement data remains local to the device display—ensuring deterministic readout latency and eliminating cybersecurity attack surfaces associated with connected peripherals. For regulated documentation, users may manually transcribe values into LIMS or ELN systems, or integrate via optional third-party analog-to-digital acquisition modules (e.g., National Instruments USB-TC01) using the device’s analog output mode (available on TL1-R-A variant). Audit trails, calibration history, and certificate retention must be managed externally per ISO/IEC 17025 clause 8.3—consistent with “manual entry” instrument classification under Annex A of EU GMP Annex 11.

Applications

• Verification and periodic checks of incubators, environmental chambers, and stability storage units per ICH Q5C
• Reference-standard temperature validation during HPLC column oven calibration and dissolution apparatus qualification (USP )
• In-process monitoring of reaction exotherms in synthetic chemistry labs where sub-0.1°C resolution informs kinetic modeling
• Calibration transfer between primary standards (e.g., PRTs) and working thermometers in metrology labs
• Temperature uniformity mapping in autoclaves and dry-heat ovens per ISO 17025 Clause 6.4.7
• Food safety validation of cold chain monitoring points during shelf-life studies (FDA Food Code §3-201.11)

FAQ

Is the TL1-R certified for use in FDA-regulated laboratories?
Yes—the included NIST-traceable calibration certificate documents measurement uncertainty per ISO/IEC 17025 and supports compliance with FDA 21 CFR Part 11 when used as a manual reference device with appropriate procedural controls.
Can the probe be immersed fully in liquid?
No—the minimum immersion depth is 11 cm (4 in) to minimize stem conduction error; full submersion beyond this depth is mechanically permissible but does not improve accuracy and may compromise seal integrity over time.
Does the instrument support data logging?
Not natively—the TL1-R is a read-only display instrument. For time-series capture, external DAQ hardware interfaced via analog output (TL1-R-A model) is required.
What is the recommended recalibration interval?
Annual recalibration is advised for GLP/GMP use; more frequent intervals (e.g., quarterly) are recommended if used daily in high-precision thermal validation protocols.
Is the CR2032 battery replaceable in the field?
Yes—the battery compartment is user-accessible with a standard Phillips #0 screwdriver; replacement requires no tools beyond the supplied Torx T5 bit for housing screws.