Troubleshooting

Troubleshooting

Issue	Likely Cause & Solution
Negative data over a longer period	Temperature or lighting changes. Ensure the bcMeter is not in direct or reflected sunlight. Do not place near radiators. If issue persists, contact support for advanced configuration.
Device keeps restarting	Power supply. USB cable impedance too high (cable too long or thin). Use a high-quality cable (<40 cm) and a 2.5A supply.
WiFi unstable or disconnects	Voltage instability (see power supply) or weak signal. The hotspot may temporarily disappear for 2–3 minutes during self-recovery — it returns automatically.
No WiFi networks listed	Reload the interface to re-initialize the network scan. Scanning pauses during active measurement — wait for the next sample cycle.
No data on graph	Sampling interval. With the default 300s sample time, the first data point appears after ~15–20 minutes (3–4 samples needed, plus initialization). Be patient.
Pump noise when stopped	Motor controller signal latch. Go to Maintenance > Reboot Device or start a new log and stop right after initialization.
Pump stall / no airflow	The device has automatic stall protection. If flow drops below threshold for 3 seconds, recovery is attempted (up to 4 times). After 4 failures, measurement stops with pump error. Check for blocked tubing, saturated filter, or hardware issues.
"Time: not synced" warning	Device clock not synchronized. Go to Maintenance and sync with your browser. Internet-connected devices sync automatically via NTP.
Email notifications not working	Verify the email service password (API key) is entered and validated in Email settings. Check that at least one valid recipient address is configured.
502 Bad Gateway error	(V1 only) Check PHP-FPM version in /etc/nginx/sites-enabled/default. Correct the fastcgi_pass line to match your PHP version.
Sensor values very low, don't change	Check voltages on LED and sensor connections. Verify 12V power is connected (the optical ADC requires it). Run calibration with a clean filter.
ADC saturation error	LED too bright or sensor oversaturated. The device attempts auto-recovery by reducing LED duty. If persistent, recalibrate with a fresh filter. Check in Developer mode if advanced LED settings need adjustment.
Overtemperature warning	Internal temperature exceeded 65°C. Move the device to a cooler location. Measurement pauses automatically and resumes when temperature drops.

Error Codes

These numerical error codes are not shown in the frontend interface. They appear in the Status API response (/api/status → error and error_msg fields) and in the System Logs (accessible from Maintenance). The interface displays a human-readable error message instead.

Code	Name	Description
0	ERR_NONE	No error
1	ERR_ADC_LOW	Sensor reading too low — filter extremely loaded
2	ERR_ADC_SATURATED	Sensor reading saturated — LED too bright; at low duty this indicates no filter is present
3	ERR_FLOW_ZERO	Pump stall, airflow below minimum
4	ERR_OVERTEMP	Temperature >65°C
5	ERR_LED_FAILURE	LED not functioning
6	ERR_ATN_LIMIT	Attenuation >120 — filter extremely clogged
7	ERR_OUTLIER_EXCESS	>80% of readings out-of-bounds

Getting Help

If your issue isn't listed here, contact jd@bcmeter.org with:

• Description of the problem
• Screenshot of the interface
• System logs (download from Maintenance > Download Logs)