Top Cloud-agri TPJ-20-LG Temperature, Humidity & Dew Point Data Logger
| Brand | Top Cloud-agri |
|---|---|
| Origin | Zhejiang, China |
| Manufacturer Type | Direct Manufacturer |
| Product Category | Domestic |
| Model | TPJ-20-LG |
| Instrument Type | Thermo-Hygrometer |
| Temperature Range | −40 °C to 120 °C (±0.4 °C accuracy, 0.1 °C resolution) |
| Relative Humidity Range | 0–100 %RH (±3 %RH accuracy, 0.1 %RH resolution) |
| Dew Point Range | −40 °C to 120 °C (±0.4 °C accuracy, 0.1 °C resolution) |
| Internal Storage | 30,000 records (Flash) + optional 4 GB microSD card |
| Communication | 2G/4G cellular network |
| Power Supply | 7.4 V / 2.8 Ah Li-ion battery (with low-voltage warning & charging protection), optional 8.4 V DC input |
| GPS | Integrated GNSS module for geotagged logging |
| Sensor Expansion | Up to 32 channels via IP67-rated hub |
| Data Upload Interval | Configurable from 5 minutes to 99 hours |
| Operating Current | 10 mA (standby), variable under active sensing |
Overview
The Top Cloud-agri TPJ-20-LG Temperature, Humidity & Dew Point Data Logger is an industrial-grade environmental monitoring instrument engineered for long-term, unattended operation in agricultural research stations, greenhouses, post-harvest storage facilities, and controlled-environment laboratories. It employs high-stability capacitive humidity sensors and platinum resistance temperature detectors (Pt1000-class) to simultaneously acquire ambient temperature, relative humidity, and derived dew point temperature—calculated in real time using the Magnus-Tetens approximation with iterative refinement per ISO 4677-2 and ASHRAE Fundamentals Chapter 1. The device operates on a deterministic embedded firmware architecture, ensuring measurement continuity during network outages through local buffering and automatic resynchronization upon reconnection. Its dual-storage architecture—comprising non-volatile Flash memory (30,000 entries) and user-expandable microSD capacity—guarantees data integrity under extended deployment cycles without manual intervention.
Key Features
- Integrated GNSS receiver providing WGS84-compliant geographic coordinates (latitude, longitude, altitude) for every logged record—enabling spatial-temporal correlation across distributed field trials.
- Cellular telemetry via certified 2G/4G modules compliant with ETSI EN 301 511 and FCC Part 22/24, supporting TLS 1.2-encrypted data transmission to cloud endpoints.
- Configurable audible alerts: Mandarin-language voice prompts for threshold violations, with programmable activation logic (e.g., sustained exceedance >5 min).
- Low-power design optimized for solar-rechargeable deployments: standby current ≤10 mA; full-sensing duty cycle configurable down to one acquisition per hour.
- Modular sensor interface supporting up to 32 analog/digital channels via IP67-rated expansion hubs—maintaining NIST-traceable calibration stability across channel additions.
- On-device LCD display with real-time visualization of timestamp, measured parameters, battery status, memory utilization, and GPS fix quality indicator.
- Built-in recharge management circuitry with overvoltage, overcurrent, and thermal cutoffs—certified to IEC 62133 for lithium-ion safety compliance.
Sample Compatibility & Compliance
The TPJ-20-LG is designed for ambient air monitoring only and is not intended for use in corrosive, explosive, or particulate-laden atmospheres exceeding IP54 ingress protection limits. All sensor elements meet RoHS 2011/65/EU and REACH (EC 1907/2006) material restrictions. Calibration certificates are provided traceable to national metrology institutes (NIM, China) via secondary standards accredited to ISO/IEC 17025. The device satisfies functional requirements outlined in ASTM D5032 (Standard Practice for Maintaining Constant Relative Humidity by Means of Aqueous Solutions) and supports audit-ready data export formats (CSV, XML) compatible with GLP/GMP documentation workflows. While not FDA 21 CFR Part 11-certified out-of-box, its encrypted cloud platform supports electronic signature integration and full audit trail generation when deployed with validated authentication protocols.
Software & Data Management
The instrument interfaces with the vendor’s cross-platform Instrument Cloud Management Platform—a browser-based C/S application accessible via HTTPS with TLS 1.3 encryption. The platform ingests time-series data with embedded GPS metadata, enabling spatiotemporal filtering, custom dashboard creation, and automated alerting via email/SMS. Data visualization includes synchronized multi-parameter trend charts, statistical summaries (min/max/mean/std dev), and overlay-capable GIS mapping. Export options include PDF reports, Excel-compatible CSV, and structured XML for LIMS integration. All data undergoes daily incremental backups with versioned snapshots retained for ≥90 days. Remote firmware updates are delivered over-the-air with SHA-256 signature verification, ensuring system integrity throughout lifecycle maintenance.
Applications
- Longitudinal microclimate profiling in protected horticulture (greenhouses, plant factories) to correlate dew point dynamics with fungal pathogen incidence (e.g., Botrytis cinerea sporulation thresholds).
- Validation of HVAC performance in seed storage vaults where dew point stability directly governs moisture migration into hermetic packaging.
- Field-based phenotyping studies requiring geo-referenced hygrothermal baselines for genotype-by-environment interaction modeling.
- Post-harvest logistics monitoring: continuous tracking of dew point depression during cold-chain transit to preempt condensation-induced spoilage.
- Educational instrumentation for undergraduate environmental physics labs demonstrating psychrometric relationships and sensor fusion techniques.
FAQ
What is the default data transmission interval, and can it be modified remotely?
The initial upload interval is factory-set to 30 minutes but is fully reconfigurable via the web platform or mobile app—no physical access required.
Does the device support external power while operating on battery backup?
Yes: the unit seamlessly switches between internal Li-ion and external 8.4 V DC input without interruption; battery charging occurs concurrently during external supply operation.
Is dew point calculated or measured directly?
Dew point is computed in real time from co-located temperature and relative humidity readings using the internationally accepted Magnus formula with coefficients optimized for atmospheric pressure ranges typical of elevations ≤3,000 m.
Can historical data be recovered if the SIM card fails or network coverage is lost?
Absolutely: all measurements remain stored locally in Flash and/or microSD until connectivity resumes, at which point buffered data is transmitted in chronological order with sequence-numbered timestamps.
Are calibration certificates included, and how often is recalibration recommended?
A factory calibration report is supplied with each unit. For applications demanding metrological rigor, annual recalibration against NIST-traceable references is advised per ISO/IEC 17025 guidelines.
