Allen-Bradley 592-TPD300 Thermal Overload Relay

Allen-Bradley 592-TPD300 is a NEMA eutectic alloy thermal overload relay (open type) engineered for three-pole motor protection in starter assemblies, with a current range of 120 to 300 A. Powered by a eutectic alloy heater element, this manual-reset overload relay trips when motor current exceeds its setpoint and requires a hand reset to restore operation, a hallmark of the 592 family. This model is explicitly a 3-pole unit for 3-phase motors and is commonly used alongside Allen-Bradley starters; current-sensing current transformers can be used with 592-TPD200/300/400/630 overload relays for accurate protection. Rockwell documentation and support materials also cover renewal parts and compatibility notes for the 592/593 overload relay family, confirming its role as a replacement option within legacy motor control schemes.