Charge Amps
How Joulo connects a Charge Amps charger through the eAPI v5, and why the meter inside is not always the source.
Charge Amps chargers connect through the Charge Amps eAPI. You sign in with your Charge Amps account. Joulo holds a partner API key alongside it, so both go on every request.
At a glance
| Property | Value |
|---|---|
| Route | Cloud API |
| API | Charge Amps eAPI v5 |
| Authentication | Joulo partner API key, plus your account login |
| Sync | Every 15 minutes |
| MID detection | Per model, from the Joulo charger catalog |
| Backfill | Automatic, to 1 January 2026 |
How the connection works
A Charge Amps login returns a short-lived JWT and a refresh token. Joulo refreshes on the refresh endpoint, and falls back to a fresh login with the credentials held in Supabase Vault when that fails. The partner API key travels on every call in its own header.
Chargers come from the owned charge-points endpoint, which returns the model as a plain string such as Halo or Aura.
What Joulo reads
Sessions come per charge point, filtered on a start and end time. Each row has a stable integer id, ISO timestamps and total consumption in kWh. The RFID tag that started the session is included where one was used.
MID certification
Joulo decides from the charger catalog, per model. The verdict on the catalog has been corrected since launch, so read mid_certified on the charger object rather than assuming from the model name.
The Charge Amps Aura has fixed internal metering. Fitting a MID meter inside the housing does not change what the charger reports over the cloud API. The certified meter is then not the source of the kWh Joulo receives. Ask Joulo support before you plan a MID upgrade around this model.
Limitations
- The API exposes no MID flag, so the verdict comes from the catalog.
- A charge point you can see but do not own is not returned by the owned endpoint, and Joulo cannot read it.