The 2TLA010033R2000 (series BT51 24 VDC) is a safety / expansion relay designed for industrial safety applications such as emergency stop circuits, safety‑interlocks, gate/guard/machine‑door monitoring, and safety output expansion. It accepts safety device inputs (e.g. emergency‑stop pushbuttons, safety‑switches, interlocks) and provides four safety‑rated outputs to simultaneously control several actuators or contactors. The relay includes internal supervision and a “test/reset” input to verify that downstream contactors or valves have actually opened before allowing a restart — ensuring a safe reset sequence. The unit is DIN‑rail mountable, compact (22.5 mm width), and suitable for integration into control cabinets.