Siemens 3TH8355-0B Industrial Contactor Relay

Siemens 3TH8355-0B Industrial Contactor Relay is a 10-contact auxiliary block for Siemens 3TH-series contactors, providing 5 normally open and 5 normally closed contacts. This auxiliary relay module extends control circuits with isolated feedback and interlocking points, enabling more complex automation and motor-control logic without loading the main contacts. It is designed to integrate with Siemens control equipment to supply signaling and control signals to PLCs, soft starters, and other automation components, helping to implement safe stop/start sequences and status monitoring. The 3TH8355-0B is part of Siemens' 3TH control-relay lineup, enabling compact installation in standard control cabinets.