TECHCAL USB Temperature Loggers: Best-Practice Guide
TECHCAL USB loggers, used right
Correct use of the ZTAG-EU single-use temperature logger in the cold chain: one activation, one report, one decision backed by data. For fruit, seafood, meat, vaccines and any temperature-sensitive product in storage and transit.
1. What it is and when to use it
The ZTAG-EU is a single-use logger in a food-grade composite pouch, fully water resistant. It records temperature continuously from origin to destination. After a one-button activation you place it next to the cargo, and it generates the report by itself when you plug it into a USB port.
Where it is used
Refrigerated containers and trucks, chilled parcels and cartons, cold storage rooms, laboratories and cold-chain warehouses.
What it monitors
Fresh fruit and vegetables, seafood and meat, vaccines and medicines, and any perishable that is temperature-sensitive.
What you get
A time-stamped record and an automatic PDF/CSV report — traceable evidence for a claim or for compliance.
2. Four steps
1. Start
Hold the START button for 3 seconds to begin recording. The green LED confirms it.
2. Place
Put the running logger next to the cargo, in the carton or on the pallet.
3. Stop
On receiving the cargo, hold STOP to close the record.
4. Read
Plug the logger into a computer USB port: the report is generated on its own, as PDF or CSV.
Start delay. The unit ships with a configurable start delay (0 minutes to 24 hours, 10 minutes by default). While it runs, the yellow LED blinks and recording has not begun. Do not release the cargo as monitored until you have confirmed that recording is active.
3. Reading the LEDs
| LED | Meaning |
|---|---|
| Green | Recording / status OK |
| Red | Alarm: a temperature threshold was crossed |
| Yellow | Start delay still running |
If the red LED comes on, at least one of the programmed alarm limits was crossed. Do not dismiss it in the field: let the record continue and check the detail in the PDF/CSV report. The alarm event is documented with a time stamp for the claim or compliance analysis.
4. Placement and handling
Do this
- Confirm the green LED is blinking before dispatch
- Place the logger near the product, at the point that best represents the thermal risk
- Use the slim design to put it inside the carton or beside the pallet
- Record the serial number or barcode in the shipping documents
- Press STOP on receipt, before reading the report
Not this
- Placing it against walls, doors or direct heat or cold sources that do not reflect the cargo
- Dispatching without confirming the record started — a yellow LED means it has not
- Reusing the logger: it is single use
- Unplugging it from USB before saving or printing the report
- Exposing it to impact or severe mechanical compression
Accuracy
Accuracy is best between −10 and 40 °C (±0.5 °C); outside that range the tolerance widens to ±0.8 °C. Let the unit settle thermally with the cargo environment before starting. A shorter logging interval gives more event resolution but uses more memory and battery.
Reading the report
The report is generated on the first USB connection, and the stop time is recorded permanently. Keep both the PDF and the CSV as traceable evidence of the shipment. The report format — PDF, CSV or both — is set at the factory according to the order.
5. Parameters set before dispatch
These are configured at the factory to match each operation. The logging interval runs from 1 minute to 24 hours, with 5 minutes as the default; the start delay from 0 minutes to 24 hours, 10 minutes by default; and the alarm thresholds according to the product. Agree these values with your SECAL adviser before you order.
6. Frequent questions
Can I reuse the logger?
No. The ZTAG-EU is single use: one activation, one record, one report.
What if I forget to press STOP?
The record continues until the memory or the battery runs out. You can still read the report, but the stop time will not reflect the moment of receipt, which weakens it as evidence.
Does it need software?
No. The report is generated automatically on the first USB connection — nothing to install and nothing to configure in the field.
Where exactly should it go?
At the point that best represents the thermal risk of the cargo, near the product. Not against walls, doors or air outlets, which show the container rather than the load.
Is it accepted for air freight?
Yes, the unit is suitable for air transport. Confirm the carrier requirements for your route.
Need temperature evidence for your shipments?
We configure interval, start delay and alarm thresholds for your product and your route.
This guide is a reference. Confirm product, dose and placement with your SECAL adviser according to your cargo and route. SECAL technical guides · PROTEXPO S.A.C. / SECAL, Lima, Peru.