What it sits between on the panel
The ABB 1SCA022657R8790 is an MCU2 motor control unit — a panel-side accessory that watches a 380-690 VAC mains feed (Vmeas) and drives field-side I/O off a 24 VDC aux supply (Uaux1), so the same module can interlock a starter or feed status back to a higher-level controller without a separate signal relay. On the input side it carries 17 digital inputs and 2 general inputs (MCU2 capability), which is enough headroom for contactor status, breaker position, and a couple of analog-style signals like thermistor or PTC feedback on a single starter cubicle. Nine LED outputs give the front-of-panel indication a wireman needs — run, fault, trip, and a handful of spares — without bolting on a separate indicator tower. Short-circuit-protected transistor outputs sit in the 20-32 mA range, so they will drive standard 24 V panel LEDs without an interposing relay.
Power and physical fit
The output voltage window of 14.0-25 VDC matches a standard 24 VDC control rail, so wiring lands on the same terminal block family as the rest of the cubicle — no exotic supply needed.