docs: show car_charging_now per charger, and how to share one charger between cars

[chalfontchubby]

Posted by Claude on behalf of @chalfontchubby.

Why

car_charging_now is what makes Predbat hold the house battery while a car is actually drawing power. It also catches a charge someone starts by hand. devices.md only showed it for Hypervolt, PodPoint, Wallbox and the old Ohme HACS integration.

#5467 showed another gap: two cars sharing one Zappi. A single charger sensor listed for both cars reads both as plugged in or charging. car_charging_exclusive then plans car 0 whichever car is actually on the charger. The docs didn't explain how to handle that.

What changes (docs only)

docs/devices.md

• A short section at the top that:
  • links to the car_charging_now reference;
  • explains that car_charging_now_response and car_charging_planned_response are each one list for every car, so values from a device example should be merged into the user's list, not replace it;
  • points to the shared-charger recipe.
• Ohme built-in HA integration: car_charging_now from sensor.ohme_{ohme_name}_status, which reads charging, with a note on Ohme Direct.
• Zappi:
  • adds car_charging_now from the plug status;
  • notes ev ready to charge, which the template's planned-response list lacks;
  • notes that re: picks an unpredictable match when there are several Zappis, and that myenergi_automatic sets these values itself.
• Fix: the Zappi car_charging_planned example was 're:sensor.myenergi_zappi_[0-9a-z]+_plug_status)'. The stray ) makes it an invalid regular expression (re.error: unbalanced parenthesis), so anyone who copied it got no plug detection.

docs/car-charging.md

• Adds car_charging_now to the list of per-car settings under Multiple Electric Cars.
• Adds a new "One charger shared by more than one car" recipe:
  • per-car template sensors gated by an input_select naming the car on the charger, with availability guards and car_charging_exclusive kept on;
  • it says where the recipe doesn't apply: chargers set up by Predbat's own integrations, whose automatic setup and charger control assume one car per charger, and a charger enrolled on its own with Octopus Intelligent.

Tesla has no example: I couldn't confirm an entity name for its integrations.

How to check

Docs only, and pre-commit passes (markdownlint, cspell). I ran several local /code-review high passes and checked the claims against the code:

• the exclusive loop (fetch.py);
• the *_response defaults;
• the 200 W threshold and kW conversion;
• overwrite=False for a car_charging_now the user has set;
• ignore_unplugged gating;
• the dispatch check's treatment of an unavailable sensor.

All anchors used match existing headings.

🤖 Generated with Claude Code

[Copilot]

🟢 Approval recommended

The documentation matches the implemented configuration and charging behavior, with no unresolved issues found.

0 open findings

What changed in this PR

Documents live EV charging detection and shared-charger configuration, addressing the setup gap highlighted by #5467.

Changes:

• Adds Ohme and Zappi car_charging_now guidance and fixes the Zappi regex.
• Adds a multi-car shared-charger recipe with guarded template sensors.

File	Description
docs/​devices.md	Expands charger-specific configuration guidance.
docs/​car-charging.md	Documents per-car settings and shared-charger setup.

🧠 Review effort: Balanced

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