The Siemens 5SU1654-7KV06 is a combined residual current and overcurrent protective device — an RCBO — in a Type A, 1+N-pole format.
Deployment context
The 70 mm depth (D=70mm) is the dimension from the DIN rail mounting surface to the front of the device — check that your enclosure depth clears this before panel layout. Type A residual-current detection handles pulsating DC fault currents, so it's suited for circuits feeding single-phase electronics, switched-mode power supplies, or variable-speed drives where a pure AC-sensing device would be blind to half-wave faults.