Residual-current monitoring unit

The inverter does not require an external residual-current device when operating. If local regulations require the use of a residual-current device, the following must be observed:

  • The inverter is compatible with residual-current devices of type B.

  • For STPS27-US-20 the rated residual current must be 270 mA or higher and for STPS60-US-20 the rated residual current must be 600 mA or higher (for information on selecting a residual-current device, see Technical Information "Criteria for Selecting a Residual-Current Device" under www.SMA-Solar.com).

  • Each inverter in the system must be connected to the utility grid via a separate residual-current device.

    Requirements for the electrical connection
    Overvoltage category