Power reduction via digital inputs

This function lets the grid operator cut feed-in power through switching contacts, usually from a ripple control receiver, that are wired to the digital inputs of an inverter or system controller. SMA systems connect the receiver through a compatible I/O system and can step feed-in power to 100%, 60%, 30% or 0%. On the SMA Data Manager M, you set this up under Grid management services by choosing digital inputs as the source for the external setpoint and assigning bit patterns to power levels. Set a fallback value or a 100% pattern, because all inputs open is an undefined state. SMA sources disagree on pulse signals. One technical note says the Data Manager M can handle pulse signals with its internal inputs, but a support article says the Data Manager needs static signals and that pulse signals must be preprocessed, for example by a Mini-PLC. On the Core1 with the SMA I/O module, the factory input patterns are D1 for 0%, D2 for 30%, D3 for 60% and all inputs open for 100%. You must also set the operating mode to active power limitation on each inverter. Solis inverters take the receiver contacts on the RJ45 DRM port. Pins 5 and 6 give on/off control, and pins 1 to 4 give 0-30-60-100% limiting, which only works with pins 5 and 6 bridged. DRM is disabled by default on Solis inverters. Enable it on each inverter, either from the display or in SolisCloud.

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• sentence 3: support check: partial - u17 supports the Grid management services path, digital inputs source and the undefined all-open state with fallback or 100%, but doesn't mention assigning bit patterns to power levels explicitly. -->