The Timing Relay (OEM Part No. 3217978851) is an electrical spare part compatible with Epiroc underground mining equipment, including Boomer 291, Simba H1354, SIMBA H1254, Boomer 281, S7D, 235 Boltec, and T1D models. Manufactured with electronic components and plastic housing, it functions as a time delay control and circuit switching component in the electrical control system. The timing relay manages electrical timing sequences, supports accurate control operations, and improves machine reliability. Designed for demanding mining environments, this replacement electrical component provides stable performance, durability, and long service life for equipment maintenance and repair applications.