testo 925 Single-Channel Thermocouple Thermometer
| Brand | testo |
|---|---|
| Origin | Germany |
| Model | 0560 9255 |
| Temperature Measurement Principle | Thermocouple (Type K) |
| Measurement Method | Contact |
| Temperature Range | -50 to +1000 °C |
| Resolution | 0.1 °C (-50 to +199.9 °C), 1 °C (remaining range) |
| Accuracy | ±(0.5 °C + 0.3 % of reading) (-40 to +900 °C), ±(0.7 °C + 0.5 % of reading) (remaining range) |
| Stability | Identical to accuracy specification |
| Operating Environment | -20 to +50 °C |
| Dimensions | 182 × 65 × 40 mm |
| Weight | 171 g |
| Power Supply | 9 V battery |
| Battery Life | 200 h (backlight off, probe connected), 68 h (backlight on, probe connected) |
| Housing Material | ABS |
| Protection Rating (with optional protective sleeve) | IP65 |
| Channel Count | 1-channel |
Overview
The testo 925 Single-Channel Thermocouple Thermometer is a precision-engineered handheld instrument designed for reliable, repeatable contact temperature measurements in industrial, HVAC, refrigeration, and sanitary system applications. Built upon the established thermoelectric principle of Type K (NiCr–Ni) thermocouples, the device delivers traceable, calibrated performance across an extended operational range of –50 °C to +1000 °C. Its architecture prioritizes field robustness and metrological integrity—featuring a high-contrast backlit LCD display, real-time min/max tracking, user-configurable acoustic alarms, and direct compatibility with a broad portfolio of certified K-type probes. As a CE-marked instrument manufactured in Germany, the testo 925 adheres to EN 61000-6-2 (immunity) and EN 61000-6-3 (emission) standards, ensuring electromagnetic compatibility in demanding technical environments.
Key Features
- Single-channel input optimized for standardized Type K thermocouples (IEC 60584-1 compliant)
- High-resolution display with adjustable backlight for low-light conditions
- Real-time simultaneous readout of current value, minimum, and maximum temperatures
- HOLD function for freezing and documenting instantaneous readings
- User-defined upper/lower limit thresholds with audible alarm activation
- Compact, ergonomic housing constructed from impact-resistant ABS polymer
- Optional protective sleeve enables IP65-rated operation (dust-tight and water-jet resistant)
- Integrated battery status indicator and low-power design supporting up to 200 hours of continuous use
Sample Compatibility & Compliance
The testo 925 requires external K-type thermocouple probes for all measurements—no built-in sensor is provided. It supports full interchangeability with testo’s certified probe ecosystem, including surface probes (e.g., clamp-on pipe sensors, spring-loaded contact probes, magnetic base sensors), immersion/penetration probes (flexible, ruggedized, high-accuracy, and IP67/IP68 waterproof variants), and air temperature probes featuring open-grid sensor geometry for rapid thermal equilibration. All compatible probes are individually calibrated and supplied with documented traceability to national standards (e.g., PTB or UKAS). The instrument itself is supplied with factory calibration certificate and conforms to ISO/IEC 17025 requirements for calibration laboratories. While not inherently 21 CFR Part 11 compliant as a standalone data logger, its measurement outputs may be integrated into validated workflows when paired with compliant data acquisition systems.
Software & Data Management
The testo 925 operates as a dedicated measurement terminal without onboard data logging or Bluetooth/Wi-Fi connectivity. However, it interfaces seamlessly with the optional testo 805i infrared printer (sold separately) for immediate on-site thermal documentation—generating timestamped, probe-identified printouts suitable for maintenance logs, commissioning reports, or audit trails. When used within regulated environments (e.g., GxP-compliant HVAC validation), users may implement procedural controls—including operator training records, periodic verification against reference standards (e.g., dry-well calibrators per ASTM E74), and documented probe calibration certificates—to satisfy GLP and GMP documentation expectations. Firmware updates are not supported; hardware revision control is maintained via serial-number-based traceability and product lifecycle documentation from testo SE & Co. KGaA.
Applications
- HVAC system commissioning and seasonal performance verification (duct, coil, and diffuser surface temperatures)
- Refrigeration circuit diagnostics (evaporator/condenser surface temps, suction/discharge line monitoring)
- Sanitary hot-water system validation (storage tank stratification, recirculation loop profiling)
- Industrial process support (furnace exhaust ducts, heat exchanger surfaces, steam trap monitoring)
- Maintenance and troubleshooting of electrical enclosures, motor windings, and bearing housings
- Building envelope thermal bridging assessments using surface-contact methodology
FAQ
Does the testo 925 include a temperature probe?
No—the testo 925 is a meter-only unit. A compatible K-type thermocouple probe must be purchased separately.
What is the recommended calibration interval?
testo recommends annual verification against a traceable reference standard in accordance with ISO/IEC 17025 practices; frequency may increase based on usage intensity and criticality of application.
Can the testo 925 be used in hazardous locations?
No—it is not intrinsically safe or ATEX-certified. Use only in non-classified areas per IEC 60079-0 general requirements.
Is the device suitable for food safety temperature checks?
Yes, when paired with appropriate stainless-steel penetration probes (e.g., testo 0600 8792) and operated within the validated range (–40 °C to +900 °C) per FDA Food Code guidelines.
How is traceability ensured for field measurements?
Each unit ships with a factory calibration certificate referencing DIN EN ISO/IEC 17025-accredited standards; end-users maintain traceability by retaining probe calibration certificates and performing periodic functional checks.
