GM-SET contactor with integral surge suppression
The Siemens 3RA9012-5AB02 is a GM-SET contactor assembly — a 3-pole, non-reversing motor starter with 1 normally-open and 4 normally-closed auxiliary contacts, rated 24 A, and fitted with an integral surge suppressor. The surge suppressor is built into the coil circuit, which means you don't need to add a separate RC snubber or varistor across the coil terminals — one less component to stock and one less failure point on the panel layout.
What the 24 A rating means for the panel
The 24 A rating on this contactor governs the continuous current it can carry in AC-3 duty (motor switching). The 1NO-4NC auxiliary contact complement gives you one set for the holding circuit or PLC feedback, and four NC sets for interlocks or status signalling — enough for a reversing starter pair or a star-delta transition without adding a separate aux block. The integral surge suppressor is wired across the coil. On a 24 V DC or AC coil, it clips the inductive kickback when the contactor drops out — that protects the PLC output or relay contact driving the coil from voltage spikes that would otherwise erode the switching element over thousands of cycles.
For a BOM freeze or a new panel design, there is no urgency to stockpile or find a substitute — the supply chain is stable.