This is a service part — the coil itself, not the full contactor assembly — so it's the component you swap when the coil fails or when you're rewiring a panel for a different control voltage.
What the control voltage rating means for fit
The 500 V AC 50 Hz control voltage is specific: it's not the common 24 VDC or 230 VAC coil found in most panels. If your control transformer or PLC output stage is 500 VAC line-to-line at 50 Hz, this coil matches. If your control bus is 400 V or 480 V, verify that the contactor's coil tolerance covers the actual voltage at the terminals — 500 V is the nominal, not the range.