TimePower TP208 Precision Chilled-Mirror Hygrometer
| Brand | TimePower |
|---|---|
| Origin | Beijing, China |
| Manufacturer Type | OEM Manufacturer |
| Origin Classification | Domestic (China) |
| Model | TP208 |
| Pricing | Upon Request |
Overview
The TimePower TP208 Precision Chilled-Mirror Hygrometer is a primary-standard moisture measurement instrument engineered for trace-level dew point determination in industrial and laboratory gas streams. It operates on the fundamental thermodynamic principle of chilled-mirror condensation: when a sample gas is cooled across a highly polished, temperature-controlled mirror surface, water vapor reaches saturation and forms a detectable dew layer at the thermodynamic dew point temperature. This physical phase-change event is monitored in real time using high-sensitivity photometric detection—measuring the abrupt change in light reflectance caused by condensate formation. As a primary method instrument, the TP208 does not rely on calibration transfer or polymer sensor drift; its measurement traceability is inherently linked to the International Temperature Scale (ITS-90) via precision Pt100 RTD mirror temperature sensing. Designed for demanding applications in power generation (SF₆ insulation gas monitoring), semiconductor purge gas qualification, pharmaceutical nitrogen blanketing, and aerospace environmental control systems, the TP208 delivers direct, SI-traceable dew point values with minimal uncertainty.
Key Features
- Chilled-mirror optical detection system with automatic dew layer recognition and real-time equilibrium validation
- Four-stage Peltier (thermoelectric) cooling architecture enabling stable mirror temperatures down to −60 °C at ambient 10 °C
- Digital fuzzy logic temperature control algorithm minimizing thermal overshoot and reducing equilibration time to 3–5 minutes
- Corrosion-resistant gas path constructed from electropolished stainless steel and fluoropolymer-sealed components, compatible with aggressive gases including SF₆, HCl, and Cl₂
- Integrated color LCD display showing simultaneous dew point (°C), volumetric moisture concentration (µL/L), real-time cooling curve, flow rate (L/h), and system status diagnostics
- Comprehensive self-diagnostic suite: alerts for suboptimal flow (outside 15–60 L/h range), low optical signal intensity (<99% reflectance), non-equilibrium conditions, and thermal instability
- Air-cooled heat dissipation design ensuring compact footprint (320 × 300 × 190 mm) and low power consumption (≤70 W)
Sample Compatibility & Compliance
The TP208 supports dry and mildly corrosive process gases—including N₂, compressed air, SF₆, Ar, He, and CO₂—within a pressure range of 10 mbar to 10 bar (1 kPa to 1 MPa). Its inert wetted materials meet ASTM E2024-20 requirements for hygrometer compatibility with reactive media. The instrument conforms to ISO 8503-2 for surface finish specification of the mirror substrate and implements hardware-level safeguards aligned with IEC 61000-4 electromagnetic immunity standards. While not certified for hazardous area installation, it is suitable for use in Class 1, Division 2 environments when installed upstream of zone boundaries. Data integrity protocols support GLP/GMP-aligned operation through timestamped measurement logs and non-volatile storage of calibration history.
Software & Data Management
The TP208 features embedded firmware with configurable data logging (internal memory retains ≥1,000 records), USB-C interface for CSV export, and RS-232/RS-485 optional modules for SCADA integration. All measurements include automatic annotation of ambient temperature, relative humidity, and barometric pressure (via external sensor input). Audit trail functionality records operator actions, parameter changes, and diagnostic events—supporting compliance with FDA 21 CFR Part 11 when paired with validated third-party data acquisition software. Firmware updates are performed via signed binary packages to ensure version control and cryptographic integrity.
Applications
- Monitoring moisture in SF₆ circuit breakers and GIS systems per IEC 60480 and IEEE C37.122.1
- Verifying dew point compliance of instrument air per ISO 8573-1 Class 2 (−40 °C dp) and Class 1 (−70 °C dp)
- Qualifying nitrogen purge gas in sterile pharmaceutical manufacturing (Annex 1, EU GMP)
- Moisture verification in cryogenic LNG transfer lines and hydrogen fuel cell feed gas
- Calibration reference for tunable diode laser (TDLAS) and aluminum oxide sensors in continuous emissions monitoring systems (CEMS)
- Research-grade humidity characterization in climate simulation chambers and material outgassing studies
FAQ
What pre-conditioning steps are required before measurement?
Prior to analysis, flush the optical chamber with high-purity nitrogen (≥99.999%) at 30 L/h for ≥15 minutes to remove residual moisture and contaminants from the mirror surface and gas path.
How is optical alignment verified during operation?
The instrument continuously monitors reflected light intensity; users must confirm “Optical Energy” remains within 99–100% on the Settings screen prior to initiating measurement.
Is the TP208 suitable for field deployment?
Yes—the robust Peltier-based thermal design, wide operating temperature range (−20 to +50 °C), and shock-absorbing internal mounting enable reliable mobile use in substations, offshore platforms, and cleanroom utility corridors.
Does the instrument require periodic recalibration?
As a primary-standard device, the TP208 does not require routine calibration; however, annual verification against a NIST-traceable dew point standard (e.g., chilled-mirror transfer standard) is recommended per ISO/IEC 17025 quality management systems.
Can it measure in vacuum conditions?
No—the minimum operating pressure is 10 mbar absolute; operation below this threshold compromises convective heat transfer and dew layer formation dynamics.
