Compatibility and integration

Integration connects building measurements and rules with charging. First identify what the building system supplies: total demand at a point, a limit for the whole point or a budget already calculated for vehicles only. These inputs mean different things.

Three ways to obtain data

• Supported metering: Shelly 3EM-63W Gen3 up to 63 A per phase, Pro 3EM 120 A v2 or Pro 3EM-400; alternatively SmartMeter connected over CIB to SmartSystem.
• Direct data integration: MQTT or the platform REST API using an agreed format and access permissions.
• Local building interface: Modbus TCP or Modbus RTU over RS485 with SmartSystem or a suitable gateway. Digital inputs can represent agreed power levels.

MQTT or Modbus support alone does not guarantee compatibility with any device. Quantities, units, phases, energy direction, timestamps, registers and acknowledgement are agreed for the specific configuration. RS485 describes the physical link; Modbus RTU describes communication over it.

Measurement and budget are not interchangeable

A BMS may send total active power in kW, current per phase or a charging budget in A or kW. For a budget, the BMS has already accounted for other appliances: EMS does not subtract them again. Fixed technical ceilings and upstream limits remain valid even if the BMS requests more power.

BMS budget and manual fallback

A valid BMS budget takes precedence for 10 minutes after the most recent budget confirmation or heartbeat confirming that budget. The same value can renew validity without an unnecessary new charger command. Consumption telemetry alone does not renew it.

The stored manual fallback applies before the first valid request and after 10 minutes without renewal. A zero BMS budget has the same validity: if it is not renewed and the manual fallback is positive, charging may resume. A fresh valid budget automatically takes precedence again. Editing the manual value while the BMS is active updates the fallback.

What a zero budget means

Zero pauses charging; it does not disable EMS or electrically isolate the station. The station may still draw auxiliary power. For digital inputs, the design must explicitly define each state and the meaning of a lost signal.

From acceptance to physical response

The integration distinguishes request acceptance, use by EMS and actual vehicle consumption. An API acknowledgement does not prove a physical power reduction. OCPP compatibility and control of the specific station are checked during commissioning; the platform manages its connection.

If required measurement is missing but the station connection works, the configured fallback limit applies, with pausing as the default. A cloud or station-connection outage prevents guaranteed delivery of a new command, and the last accepted profile may remain. Recovery requires fresh live inputs.

Where to go next

Cloud EMS technical guide · Product guide (PDF, Slovak) · Technical guide (PDF, Slovak).