wallmonitor

A local-only companion for the Tesla Wall Connector Gen 3 that grew well beyond reading data off the charger: it records everything the device reports, turns that history into a thermal model fitted to your install, forecasts derates before they happen (with the charge-current cap that avoids them), watches for connector degradation with honest statistics, and pushes actionable warnings to your browser or phone.

Everything stays on your machine and your LAN: the only network traffic is HTTP GETs to the charger's local API, storage is a local SQLite file, and the web UI serves no external assets (no CDNs, fonts, or analytics).

Try it in 30 seconds

No hardware needed — demo mode runs a built-in charger simulator:

uvx wallmonitor --demo

Then open http://127.0.0.1:8480.

Against your real Wall Connector (find its IP in your router, or use the TeslaWallConnector_XXXXXX.local hostname; add --split-phase on a North American split-phase install):

uvx wallmonitor --host 192.168.1.50 --split-phase

All history lands in a single wallmonitor.db SQLite file — back up that one file and you have everything. For every option, and for running it as a systemd service on an always-on box, see Running wallmonitor.

At a glance

• Full-fidelity recording — every response stored with its complete raw JSON
• Live dashboard (SSE) with rolling charts, an active-alert banner, and a live derate-forecast chart: measured handle temperature against the model's projected plateau and the trip threshold, projection drawn forward so the predicted trip intercept is visible on the chart
• Session review: energy, peak/average power, per-phase telemetry, drillable charts
• Event timeline with range presets, category filters, and paging
• Alert decoding and EVSE-state labels, each marked verified vs community-reported
• Wi-Fi health history and connectivity events
• Thermal derate forecast — a per-install fitted model predicts alert 40 live and suggests the highest current that avoids the 50% foldback
• Automatic derate prevention — an optional daemon caps the vehicle's charge current through a least-privilege BLE pairing when the forecast firms up, and restores it once the risk clears
• Degradation watch — ambient-corrected heat-rise trend with confidence intervals and a verified-baseline anchor, so "getting worse" is a statistical claim, not a vibe
• Actionable notifications, local-only — browser push and LAN webhook/self-hosted ntfy for phones, with a systemd + Docker deploy recipe
• Resilience: seamless restarts, downtime recorded as explicit gap events, sensor-glitch quarantine

Works out of the box — everything else is additive

The core needs nothing but the charger. Integrations are optional, degrade gracefully when absent, and the absence paths are covered by the test suite: without an ambient sensor the charger doubles as its own thermometer, with no webhook configured notifications are a tested no-op, and TeslaMate / ntfy / ESP32-BLE each plug into a generic interface (POST /api/ambient, a plain LAN webhook, a REST call) rather than being wired into the core.

Documentation

Tests

uv run pytest

The suite runs the full pipeline against the simulator — polling, session detection, alert lifecycle, the web API, and the thermal model end to end.

License

MIT. Built on the tesla-wall-connector library (MIT, by Einar Bragi Hauksson).