Rated current and coil — what drives the fit
The A16-30-10-81: The '30 A' in the order code refers to the frame size, not the operational current — the actual motor load it can switch in AC-3 duty is 17 A, so size it against the full-load current of the motor, not the frame number.
Panel fit and mounting — what to check before ordering
The 24 V AC coil draws inrush current at pickup — verify that the control transformer supplying the coil has enough VA headroom to handle the inrush without voltage sag. The single NO auxiliary contact is wired to the front terminals; if your circuit needs more than one auxiliary, an add-on block is required.