Truelab BT-2 Dual-Channel Temperature and Relative Humidity Meter

Overview

The Truelab BT-2 Dual-Channel Temperature and Relative Humidity Meter is a compact, field-deployable environmental monitoring instrument engineered for continuous, real-time measurement of ambient temperature and relative humidity in non-critical and general-purpose environments. It operates on the principle of resistive-capacitive sensing for humidity detection and precision thermistor-based measurement for temperature acquisition. The device features two independent temperature inputs—one internal sensor and one external probe—enabling simultaneous monitoring of two spatially distinct thermal conditions, while the integrated capacitive humidity sensor provides stable response across a broad RH range. Designed for operational simplicity rather than laboratory-grade metrology, the BT-2 delivers reliable data for environmental verification, storage condition logging, and basic climate surveillance in settings where traceable calibration and regulatory compliance are not mandated.

Key Features

• Dual-channel temperature capability: Internal sensor (–30 °C to +50 °C) and detachable external probe (–50 °C to +70 °C) support comparative or distributed thermal assessment.
• Single-point relative humidity measurement with 20–99 % RH range and 1 % RH resolution, optimized for ambient indoor and semi-controlled environments.
• Large backlit LCD display (81.5 × 64.5 mm active area) ensures legibility under low-light conditions and at viewing angles up to ±60°.
• Memory functions include high/low temperature and humidity tracking with manual reset; values persist through power cycling.
• Configurable unit selection: direct switching between Celsius and Fahrenheit scales without recalibration or firmware intervention.
• Integrated real-time clock with programmable alarm function supports time-stamped observation intervals and scheduled environmental checks.
• Low-power design compatible with a single 1.5 V AAA alkaline cell, enabling >12 months of typical operation under intermittent readout conditions.

Sample Compatibility & Compliance

The BT-2 is intended for use with ambient air samples only; it is not suitable for corrosive, condensing, dusty, or high-velocity airstreams. No sample preparation or conditioning is required. As a general-purpose thermo-hygrometer, it does not comply with ISO 17025, ASTM E2234, or IEC 60751 Class A/B specifications. It is not validated for GxP environments, nor does it support audit trails, electronic signatures, or 21 CFR Part 11 compliance. Its accuracy tolerances (±1 °C temperature, ±5 % RH at 25 °C) align with ISO 7726 Category III (general comfort and storage monitoring) rather than Category I (precision laboratory applications). Calibration is user-performed via offset adjustment; NIST-traceable certificate issuance is not supported.

Software & Data Management

The BT-2 operates as a standalone, embedded-system instrument with no USB, Bluetooth, or wireless connectivity. All data remain local to the device: high/low memory registers retain extremum values until manually cleared, and the clock maintains time integrity independently. No proprietary software, drivers, or cloud interface is provided. Data export is not supported; users must manually record readings from the display. Firmware updates are unavailable. For integration into larger monitoring networks, the BT-2 may serve as a reference node for periodic visual verification—however, automated data aggregation requires external manual transcription or third-party datalogging adapters (not supplied).

Applications

• Warehouse and cold-storage facility spot-checking: verifying nominal temperature bands during receiving, staging, and long-term holding of non-pharmaceutical goods.
• Office and residential climate awareness: identifying seasonal drift, HVAC performance anomalies, or localized microclimates near windows or mechanical equipment.
• Educational laboratories: introducing fundamental concepts of psychrometrics, thermal equilibrium, and sensor response time in undergraduate physics or environmental science curricula.
• Archival and document storage rooms: supporting passive monitoring of RH excursions that may accelerate paper degradation or media oxidation.
• Transportation validation pre-checks: quick verification of ambient cabin or container conditions prior to loading temperature-sensitive but non-regulated cargo (e.g., consumer electronics, textiles).

FAQ

Does the BT-2 support data logging or PC connectivity?
No. The device has no serial, USB, or wireless interface. All measurements are displayed in real time and retained only as min/max memory values.
Is the external temperature probe included by default?
Yes—the BT-2 ships with one integrated external thermistor probe on a 1.2 m PVC-insulated cable with a 3.5 mm mono jack connector.
Can the device be wall-mounted or fixed in place?
It includes two recessed mounting holes (M3 thread) on the rear housing and a built-in kickstand for tabletop use; however, no mounting hardware is supplied.
What is the recommended recalibration interval?
Truelab recommends annual functional verification against a reference hygrometer and dry-wet bulb comparator; formal recalibration is not offered due to the device’s non-adjustable sensor architecture.
Is the display readable in direct sunlight?
The monochrome LCD lacks anti-glare coating or transflective enhancement; readability degrades significantly under incident solar irradiance exceeding 10,000 lux.