GILL MetPak Base Portable Multi-Parameter Weather Station

Overview

The GILL MetPak Base is a compact, low-power, multi-parameter environmental sensor system engineered for autonomous meteorological monitoring in remote or resource-constrained locations. Though officially discontinued and succeeded by the enhanced MetPak Pro platform, the MetPak Base remains referenced in legacy installations and technical documentation due to its adherence to internationally recognized measurement principles. It operates on passive (natural) aspiration for temperature and relative humidity sensing—implemented via a WMO-compliant triple-layer double-louvered radiation shield—to minimize solar loading and convective bias. Atmospheric pressure is measured internally within a thermally stabilized, ventilated housing to reduce diurnal thermal lag. The unit integrates calibrated industrial-grade sensors traceable to national metrology standards and outputs digital serial data via SDI-12, RS-232, and RS-422 protocols—enabling direct interfacing with third-party data loggers (e.g., SpaceLogger), display units (e.g., WS-15A), or SCADA systems without protocol translation hardware.

Key Features

• Compact, ruggedized aluminum enclosure rated for outdoor IP65 operation across –30 °C to +60 °C ambient conditions
• Natural-aspiration temperature and humidity sensing using high-stability capacitive RH and Pt100 RTD elements housed in a triple-louvered, double-wall solar radiation shield
• Barometric pressure transducer mounted inside a thermally buffered, ventilated cavity to mitigate thermal drift and hysteresis
• Low average power draw (< 1.5 W typical), supporting extended battery- or solar-powered deployments
• Modular mechanical architecture: integrated mounting bracket includes a weatherproof terminal junction box for field wiring of sensor outputs and optional heater circuits
• Standard serial communication suite: SDI-12 (for compatibility with Campbell Scientific and similar loggers), RS-232 (point-to-point), and RS-422 (multi-drop, noise-immune)
• Optional heated junction box interface for seamless integration with GILL’s heated wind sensors—including WindSonic M, WindObserver 70, WindMaster, and WindMaster Pro—ensuring ice-free operation in sub-zero environments

Sample Compatibility & Compliance

The MetPak Base was designed to support long-term climatological observation in accordance with World Meteorological Organization (WMO) No. 8 guidelines for surface-based instrumentation. Its radiation shield geometry and airflow characteristics comply with ISO 7726 (Ergonomics of the thermal environment) and BS EN 13791 (Meteorological instruments – Specifications for temperature and humidity sensors). While not certified for regulatory compliance under FDA 21 CFR Part 11 or EU Annex 11, its deterministic serial output format, stable calibration history, and documented sensor uncertainty budgets make it suitable for non-GxP environmental baseline studies, ecological monitoring, and academic field research where traceability and repeatability—not formal audit readiness—are primary requirements. All internal sensor calibrations were performed at GILL’s UK facility against NPL-traceable reference standards.

Software & Data Management

The MetPak Base does not include embedded firmware-based configuration utilities or onboard data storage. Instead, it functions as a deterministic sensor node: raw parameter values (temperature in °C, relative humidity in %RH, barometric pressure in hPa, dew point in °C) are streamed at user-configurable intervals (default 10 s) via ASCII-formatted serial frames. Data parsing is supported natively by industry-standard logging platforms including Campbell Scientific LoggerNet, HOBOware, and generic terminal emulators (e.g., PuTTY, Tera Term). For time-synchronized long-term archiving, integration with SpaceLogger or similar timestamp-capable recorders is recommended. Firmware updates were historically delivered via RS-232; no over-the-air (OTA) capability exists. Configuration parameters (baud rate, output interval, unit scaling) are set via simple ASCII command strings per GILL’s published Command Reference Manual v3.2.

Applications

• Remote infrastructure monitoring: transmission line corridors, pipeline right-of-ways, and unmanned substations requiring ambient thermal and pressure context
• Ecological field stations: phenology studies, eddy covariance ancillary measurements, and microclimate profiling in forest canopies or alpine zones
• Educational meteorology labs: hands-on instruction in sensor physics, serial communication protocols, and WMO observational practices
• Aviation support: non-certified wind/temperature trend logging at private airstrips or UAV launch sites
• Renewable energy siting: preliminary solar irradiance proxy estimation via dew point depression analysis and boundary layer stability assessment
• Historical network continuity: replacement or cross-calibration node for aging MetPak Base installations prior to full migration to MetPak Pro

FAQ

Is the MetPak Base still available for purchase?
No—GILL discontinued the MetPak Base in 2018. Only refurbished or legacy inventory units may be sourced through authorized distributors; no new manufacturing or warranty support is provided.
Can I integrate the MetPak Base with modern IoT gateways?
Yes—via RS-422-to-MQTT or SDI-12-to-LoRaWAN protocol converters; however, GILL does not supply or endorse specific gateway firmware.
Does it support NMEA 0183 or Modbus RTU?
No—only SDI-12, RS-232, and RS-422 ASCII protocols are implemented. Protocol conversion requires external hardware.
What is the typical measurement uncertainty for temperature and humidity?
Per original datasheet: ±0.2 °C for temperature (–20 °C to +50 °C), ±2 %RH for humidity (10–90 %RH, 23 °C), and ±0.5 hPa for pressure (800–1100 hPa).
Is there a calibration certificate included?
Factory calibration certificates were supplied with each unit at time of original sale; no recalibration service is offered post-discontinuation. Users are advised to perform field verification using portable reference standards.