Jingcheng Huatai HT-TWD Soil Temperature Rapid Measurement Logger

Overview

The Jingcheng Huatai HT-TWD Soil Temperature Rapid Measurement Logger is a field-deployable, single-channel data logging system engineered for precise, long-term monitoring of soil thermal profiles in agricultural, ecological, and environmental research applications. It operates on the principle of high-stability thermistor-based temperature sensing, calibrated to meet ISO/IEC 17025 traceable accuracy standards (±0.5 °C over −40 °C to +100 °C). Unlike basic digital thermometers, the HT-TWD integrates embedded real-time clock synchronization, non-volatile data storage architecture, and configurable sampling logic—enabling autonomous operation across diverse deployment scenarios including unattended greenhouse monitoring, watershed-scale irrigation trials, and permafrost boundary studies. Its compact form factor (140 × 120 × 35 mm) and 1 kg mass support handheld survey use as well as fixed-site installation, while the dual-power design (rechargeable Li-ion + optional AC adapter) ensures operational continuity under variable field conditions.

Key Features

• Graphical monochrome LCD display with full Chinese menu navigation—supports real-time viewing of measured temperature, timestamp, battery level, remaining storage capacity, and recorded entry count
• Configurable acquisition modes: manual-triggered logging or time-scheduled automatic recording (interval adjustable from 5 minutes to 99 hours)
• Robust on-device data retention: 30,000 measurement entries stored on removable 4 GB TF card with built-in power-fail protection—no data loss during unexpected shutdown
• Modular sensor interface compliant with RS485 industrial protocol; supports daisy-chaining up to 32 sensors via optional hub (each channel maintains independent calibration and accuracy)
• USB 1.1 host interface for direct PC connection—enables rapid data export without proprietary drivers
• Expandable functionality suite: optional GPS geotagging, voice feedback alerts, and GPRS-enabled cloud telemetry with web-based dashboard and mobile application access
• Environmental resilience: sensor probe rated for continuous operation at −40 °C to +80 °C ambient; stainless-steel sheath with ≥25 cm insertion depth ensures representative volumetric thermal sampling

Sample Compatibility & Compliance

The HT-TWD is validated for direct insertion into mineral soils, loam, clay, sandy substrates, and organic growing media—including peat-based horticultural mixes and compost-amended fields. Its probe geometry and thermal mass balance minimize air-gap artifacts and ensure stable equilibration within 2 seconds (per manufacturer specification). While not certified to IEC 60529 IP ratings, the instrument meets functional requirements for outdoor use under covered or sheltered conditions (e.g., beneath rain shields or within weatherproof enclosures). Data integrity complies with GLP-aligned practices: all logged entries include immutable timestamps, sequential record IDs, and sensor-specific metadata. Optional GPRS transmission supports audit-ready data lineage when integrated with cloud platforms adhering to ISO 27001 information security controls.

Software & Data Management

The included Windows-compatible upper-computer software provides raw data visualization, statistical summary (min/max/mean), trend curve plotting with zoom/pan functionality, and customizable time-range filtering. All datasets export natively to .CSV and Microsoft Excel (.XLSX) formats—facilitating integration with third-party analysis tools such as R, Python (Pandas), MATLAB, or commercial agronomic modeling suites. The software enforces structured metadata tagging (location ID, operator name, sensor serial number) and supports batch import/export workflows suitable for multi-site longitudinal studies. For regulated environments, optional GPRS-enabled firmware versions include encrypted TLS 1.2 transmission and user-access logs compatible with FDA 21 CFR Part 11 electronic record requirements when deployed with appropriate platform-level authentication and audit trail configuration.

Applications

• Smart irrigation scheduling based on root-zone thermal dynamics
• Phenological monitoring in controlled-environment agriculture (CEA) and vertical farms
• Soil respiration rate estimation via temperature-driven Q₁₀ modeling
• Validation of numerical heat-transfer models in vadose zone hydrology
• Long-term climate impact assessment in grassland, forest, and tundra ecosystems
• Calibration reference for distributed wireless sensor networks (WSNs)
• Quality assurance in nursery stock production and seed germination trials

FAQ

What is the maximum recommended burial depth for the HT-TWD sensor probe?

The probe is designed for insertion depths of 5–30 cm; optimal performance is achieved at ≥25 cm to minimize diurnal surface fluctuation interference.
Can the device log data without being connected to a computer?

Yes—the HT-TWD operates autonomously once configured; no continuous PC connection is required for scheduled or manual logging.
Is the USB interface compatible with modern Windows 10/11 systems?

Yes, it uses standard USB 1.1 CDC ACM class drivers—no additional software installation is needed beyond the provided application.
How does the system handle battery depletion during extended deployments?

The unit implements low-voltage cutoff at 6.0 V and retains all stored data in non-volatile memory—even after complete discharge.
Are calibration certificates available for traceable metrology compliance?

Factory calibration reports (including reference standard ID, uncertainty budget, and test points) are supplied upon request and conform to CNAS-accredited laboratory practice.