Interface
Web Interface Overview
The bcMeter web interface is a real-time dashboard accessible from any browser on the same network. It provides measurement visualization, device control, and configuration — all from your phone or computer.
Try the live demo: bcmeter.org/demo
Dashboard Elements
The main screen consists of five areas:
- Control Bar — Buttons to Start/Stop measurement, access Log Files, Settings, and Maintenance.
- Status Panel — Device state, filter loading, and time synchronization status.
- Statistics — Real-time averages: 1h Average, Session Average, Peak Value.
- Live Plot — Visualizes Black Carbon concentration over time.
- Plot Controls — Download options, zoom reset, axis scaling, log selection, Y-axis parameter assignment, and denoise sliders.
Status Indicators
Device Status
| Status | Meaning |
|---|---|
| Ready | Device is idle. Pump is off. |
| Initializing | Pump is priming and the optical chamber is warming up. Data is not yet recorded. |
| Running | Active measurement. Data is being saved. |
| Error | System error detected. Check System Logs in the Maintenance menu. |
Time Sync Status
A time synchronization indicator is displayed in the status bar. If the device clock is not synced, it shows "Time: not synced" in red. Accurate timestamps are essential for data analysis — use Maintenance > Time Synchronization to sync the device clock with your browser.
Filter Loading Status
The "Filter" indicator displays the loading percentage of the filter strip. Colors indicate loading level:
| Color | Loading | Meaning |
|---|---|---|
| Green | 0–30% | Filter is clean. Signal quality is optimal. |
| Orange | 30–70% | Loading increasing. Mathematical compensation is active. Prepare a replacement. |
| Red | 70–85% | Heavily loaded. Compensation becomes less reliable. Replace soon. Email alert sent every 12h when >70%. |
| Dark | 85%+ | Near saturation. Replace immediately. |
Data Visualization
Plot Behavior
The interactive graph visualizes time-series data. Due to the analog nature of the signal and signal-to-noise ratio limitations, the graph typically shows a jagged, fluctuating line. The rolling average is closer to the "real" value.
After starting a measurement, it takes approximately 3–4 samples before the graph appears. At the default 300s (5 min) sample interval, the first data appears after 15–20 minutes.
- Zoom: Click and drag to zoom in. Double-click to reset.
Plot Controls
Located below the live plot:
- Download View: Export current view as CSV, PNG, or SVG.
- Reset Zoom: Restore default view after zooming.
- Axis Scaling: Manually override automatic Y-axis scaling when peaks compress the view.
View Log
Dropdown to select which session log to display — current session or any previous log file stored on the device.
Y-Axis Controls
Accordion menus (Y1, Y2) to assign plot parameters and adjust filtering:
- Axis Selection: Choose which parameter to display on each axis (see Plot Parameters).
- Denoise: Median filter slider per axis to smooth the signal.
- Direct emission monitoring: Keep below 4 for fast response.
- Ambient monitoring: Higher settings acceptable for smoother signal.
Plot Parameters
The following parameters can be assigned to Y1 or Y2 axes:
| Parameter | Description |
|---|---|
| Reference (880nm) | Light intensity from the 880nm LED through the clean portion of the filter — baseline for comparison. Optional: 520nm, 370nm if multi-wavelength hardware installed. |
| Sensor (880nm) | Light intensity after passing through the particle-loaded spot. |
| Attenuation (880nm) | Calculated reduction in light intensity caused by absorbing particles. |
| BC Unfiltered (880nm) | Real-time black carbon concentration without smoothing. |
| Black Carbon (880nm) | BC concentration in ng/m³, with rolling average applied. |
| Relative Load | Filter spot saturation level (%), indicating when replacement is needed. |
| Ångström Exponent | Ratio indicating aerosol source characteristics (requires multi-wavelength hardware). |
| Temperature (°C) | Internal operating temperature — important for measurement stability. |
| Humidity (%) | Relative humidity inside the device (if sensor equipped). |
| Air Flow (l/min) | Current airflow rate through the filter (if flow sensor equipped). |