KHC-2000B Ambient Air Sampler
| Origin | Jiangsu, China |
|---|---|
| Manufacturer Type | Authorized Distributor |
| Model | KHC-2000B |
| Price | USD 860 (FOB) |
Overview
The KHC-2000B Ambient Air Sampler is an electronically controlled, microprocessor-driven low-flow air sampling instrument engineered for regulatory-compliant collection of gaseous and particulate pollutants from ambient environments. It operates on the principle of constant-flow volumetric sampling—maintaining precise, user-defined airflow rates across variable backpressure conditions (e.g., filter loading, temperature drift, or power supply fluctuations). Unlike legacy mechanical glass rotameter-based systems, the KHC-2000B employs closed-loop feedback control of a brushless DC motor coupled with a calibrated mass flow sensor, enabling real-time dynamic compensation to sustain flow stability within ±2% of setpoint over its operational range. Designed for field-deployable continuous or time-integrated monitoring, it supports both single- and multi-segment programmable sampling protocols required by national ambient air quality standards (e.g., China’s HJ/T 374–2007, US EPA Method TO-15 and IO-3.2).
Key Features
- Microcontroller-based embedded system with full中文-to-English bilingual firmware interface (default English UI with optional localized language support via firmware update)
- Large-format LCD display (128 × 64 pixels) with intuitive menu navigation and contextual on-screen prompts during calibration or parameter entry
- Programmable sampling modes: single-stage fixed-flow, multi-stage sequential sampling with independent flow/time/interval settings per stage
- Integrated thermal mass flow sensor with automatic zero-drift correction and voltage-compensated motor drive—eliminates reliance on analog glass rotameters
- User-accessible software calibration suite: enables field recalibration of flow response curves using NIST-traceable reference calibrators (e.g., dry gas meters or primary sonic nozzles)
- Robust aluminum alloy chassis with IP54-rated enclosure for outdoor deployment; operating temperature range: −10 °C to +50 °C
Sample Compatibility & Compliance
The KHC-2000B is compatible with standard 47 mm and 90 mm diameter filter substrates (quartz fiber, Teflon, PVC), sorbent tubes (e.g., Tenax TA, Carbopack B), and impingers for gaseous analyte capture. It meets mechanical and performance requirements outlined in ISO 7708:1995 (airborne particles — size-selective sampling criteria), EN 12341:2014 (ambient air—measurement of PM10 and PM2.5), and aligns with data integrity expectations under GLP and ISO/IEC 17025 laboratory accreditation frameworks. While not intrinsically certified for hazardous area use, it may be deployed in non-classified ambient zones per IEC 60079-0 general requirements.
Software & Data Management
Internal firmware stores up to 1,000 sampling event logs—including date/time stamp, target flow rate, actual mean flow, total sampled volume, battery status, and error flags—with timestamped audit trail functionality. Data export is supported via USB-C interface to PC using vendor-provided Windows-compatible configuration utility (no cloud dependency). The software enforces secure parameter locking (password-protected admin mode), supports CSV-formatted batch export, and generates ISO/IEC 17025-aligned metadata headers for traceability. Firmware updates are performed offline via signed binary files to ensure integrity and compliance with FDA 21 CFR Part 11 electronic record controls where applicable.
Applications
- Regulatory ambient air quality monitoring networks (PM2.5, PM10, VOCs, SO2, NOx)
- Indoor air quality (IAQ) assessment in schools, offices, and healthcare facilities
- Source apportionment studies requiring synchronized multi-location sampling
- Method validation and inter-laboratory comparison exercises
- Field calibration verification of continuous ambient analyzers (e.g., beta attenuation monitors, chemiluminescence NOx analyzers)
- Occupational hygiene surveys where personal or area sampling must adhere to OSHA ID-121 or NIOSH 0500/0600 methodologies
FAQ
Does the KHC-2000B require annual factory recalibration?
No—users may perform on-site flow calibration using a NIST-traceable primary standard; however, annual verification against accredited reference equipment is recommended for ISO/IEC 17025 compliance.
Is the device compatible with lithium-ion battery packs for extended unattended operation?
Yes—optional external 12 V LiFePO4 battery modules (sold separately) support >24 h continuous sampling at 1.0 L/min; internal rechargeable Ni-MH backup maintains clock and memory during main power loss.
Can sampling parameters be locked to prevent unauthorized modification?
Yes—admin-level password protection secures all critical settings including flow setpoints, time scheduling, and calibration coefficients.
What communication protocols does the USB interface support?
CDC ACM (Virtual COM Port) class—no proprietary drivers required on Windows 10/11, macOS 12+, or Linux kernel ≥5.4.
Is firmware source code available for third-party integration?
No—firmware is proprietary and digitally signed; however, a documented REST-like HTTP API (via optional Ethernet module) is available for SCADA system integration under OEM agreement.
