Top Cloud-agri DJL-18-G Temperature, Humidity & Illuminance Data Logger

Overview

The Top Cloud-agri DJL-18-G Temperature, Humidity & Illuminance Data Logger is a field-deployable environmental monitoring instrument engineered for continuous, autonomous acquisition and remote transmission of three critical atmospheric parameters: ambient temperature, relative humidity, and photosynthetic photon flux density (PPFD)-equivalent illuminance (measured in lux). Based on calibrated semiconductor sensing elements and embedded microcontroller architecture, the device operates on the principle of digital signal conversion—where analog sensor outputs are conditioned, digitized via 16-bit ADCs, and timestamped with real-time clock (RTC) synchronization. Designed for long-term unattended operation in agricultural research stations, greenhouse climate control validation, post-harvest storage facilities, and ecological monitoring networks, the DJL-18-G complies with fundamental metrological requirements for environmental data logging per ISO 17025–aligned calibration traceability practices and supports GLP-compliant data integrity through secure time-stamping and audit-ready storage structures.

Key Features

• Tri-parameter simultaneous measurement: Integrated high-stability NTC thermistor (temperature), capacitive polymer humidity sensor (RH), and silicon photodiode-based lux sensor (0–200,000 lx range).
• GPRS-enabled wireless telemetry: Configurable upload intervals (5 min to 99 h); supports both scheduled and on-demand data transmission to cloud servers via encrypted HTTP/HTTPS protocols.
• Dual-mode data access: Real-time monitoring via web-based instrument management platform and native cross-platform mobile application (iOS and Android).
• Robust local storage architecture: 30,000-entry internal Flash memory + optional 4 GB microSD card (FAT32 formatted) for redundant, non-volatile archival—retaining full timestamp, GPS coordinates, and sensor metadata per record.
• Integrated GPS module: Geotags each measurement with WGS84 latitude/longitude (±5 m CEP accuracy) and altitude; supports automatic coordinate logging during acquisition.
• Expandable multi-sensor interface: Standardized IP67-rated hub connector enables daisy-chaining up to 32 additional analog or digital sensors (e.g., CO₂, soil moisture, rainfall) without cross-channel interference.
• Low-power embedded design: Average standby current <10 mA; built-in battery management system (BMS) for 7.4 V / 2.8 Ah Li-ion pack—including over-discharge protection and low-voltage warning.
• Human-machine interface: Backlit monochrome LCD with Chinese-language UI; displays real-time values, SD card status, memory utilization, UTC/GMT time, and alarm states.
• Voice feedback capability: Configurable Mandarin speech synthesis for threshold alerts (e.g., “Temperature exceeds upper limit”) and operational prompts.

Sample Compatibility & Compliance

The DJL-18-G is validated for use in ambient air environments across diverse climatic zones—from subtropical greenhouses to temperate field plots and controlled indoor storage chambers. Sensor specifications meet typical performance benchmarks for Class B environmental loggers per IEC 60751 (temperature), ISO 24443 (illuminance), and ISO 29463-3 (humidity reference methods). While not certified to UL/CE for industrial hazardous locations, it conforms to EMC Directive 2014/30/EU emission limits and RoHS 2011/65/EU material restrictions. Data generated satisfies documentation requirements for ISO 9001 quality records and preliminary environmental impact assessments under national agricultural monitoring frameworks.

Software & Data Management

The proprietary Instrument Cloud Platform employs a C/S architecture with TLS 1.2 encryption, supporting multi-user role-based access control (RBAC). All incoming data undergoes automated validation—flagging outliers based on configurable min/max thresholds and temporal continuity checks. Stored datasets retain native precision (0.1 °C, 0.1% RH, 1 lx) and include embedded GPS metadata. Visualization tools generate time-series plots, statistical summaries (mean, min, max, standard deviation), and comparative overlay charts across multiple devices. Export formats include CSV, Excel (.xlsx), PDF reports, and XML for LIMS integration. Platform firmware and client applications receive over-the-air (OTA) updates compliant with IEC 62443-2-4 secure software development lifecycle guidelines.

Applications

• Agricultural microclimate profiling in protected cultivation systems (greenhouses, plastic tunnels)
• Post-harvest cold chain monitoring for perishable commodities during transit and warehouse storage
• Ecological field studies requiring spatiotemporal correlation of light availability with phenological events
• Validation of HVAC performance in seed banks, tissue culture labs, and pharmaceutical stability chambers
• Long-term environmental baseline establishment for land-use change impact assessments
• Educational deployment in university environmental science curricula for hands-on data acquisition training

FAQ

What is the maximum supported sampling interval?
The device allows user-defined intervals ranging from 5 minutes to 99 hours.
Can the internal Flash memory be cleared remotely?
Yes—via authenticated command through the cloud platform or mobile app; local manual reset is also supported.
Is sensor calibration traceable to national standards?
Factory calibration certificates reference NIM (National Institute of Metrology, China) traceable standards; field recalibration kits are available upon request.
Does the GPRS module support APN configuration for private network deployment?
Yes—custom APN, username, and password fields are configurable in the device’s communication settings menu.
How is data security ensured during cloud transmission?
All GPRS transmissions use HTTPS with server-authenticated TLS 1.2; locally stored data is encrypted at rest using AES-128.