Quick answer: The testo 174-T creates a time-stamped environmental record. The 174 T logs temperature; the 174 H additionally records relative humidity. Data quality depends on placement, programming and recovery of the whole recording.
What makes the testo 174-T different
The testo 174 T is a compact temperature logger, not a live food-core probe. Its recorded history depends on programming, response time, placement and subsequent software download. For the supplementary product check, see the guide to food core-temperature checks.
Prepare and carry out the measurement
- Identify the exact logger variant and compatible readout method, then synchronize the clock and units.
- Select a sample interval and start condition matched to the expected event duration, memory and battery life.
- Mount where conditions represent the monitored product or space rather than the door or fan jet, and run a short functional check.
- Export the readings, document gaps/excursions and compare them with the site’s own limits and process context.
Model-specific use and interpretation
Identify the exact hardware variant/software, synchronize date and time, select the sample interval and appropriate start mode, mount the logger at a representative air location and verify one test recording before deployment.
An air logger measures the local environment around its sensor, not automatically the product core temperature. Humidity peaks can arise from local temperature changes and access events.
An excursion visible in the graph may reflect door opening or warm air near the sensor. Use the product’s documented acceptance limits and a supplementary product check where required.
Worked example (hypothetical)
Hypothetical plan: logging every five minutes for a seven-day period requires 7 × 24 × 12 = 2,016 timestamps per channel, before any additional setup or metadata records.
Logger placement changes what a cold-chain record means
The 174 T records air temperature at its own sensor; a door-side placement can show access peaks that the product core does not experience. Record its mount location and sampling interval, then use the exported trace to identify the time and duration of excursions. A single peak should trigger investigation under the site’s quality plan, not automatic dismissal or automatic disposal. For practical guidance on representative placement and stabilization, see accurate ambient air temperature measurement.
Interpretation: At a ten-minute sample interval, an event lasting two minutes may occur entirely between readings, so the log cannot exclude every short excursion.
Limits and safety
Follow the exact instrument manual and the equipment manufacturer’s acceptance criteria. The example is not field evidence, a legal limit or a commissioning target. Work on energized electrical equipment, combustion systems, charged refrigerant circuits or hot surfaces requires qualified personnel and the site’s approved protective procedures.