The 8-pole NFZB auxiliary contactors meet the latest standards for rolling stock and allow installation in passenger or driver's cabs of trains that frequently travel in tunnels or underpasses. They are used to switch auxiliary and control circuits (positively guided contacts available). They meet all the important standards for rolling stock: IEC 60947-4-1, IEC 60947-5-1, IEC 60077-1/-2 and applicable parts of the EN 50155 standards, shock and vibration resistance according to IEC 61373 Cat. 1, Class B. They also achieve the highest levels of fire and smoke behavior while complying with the European standard EN 45545-2 (HL2 hazard levels) when mounted in groups. They have an electronic coil interface that allows a wide control voltage range and can handle large control voltage fluctuations. NFZB auxiliary contactors have built-in overvoltage protection and do not require additional suppression elements.