Eaton ETR4-51-A timing relay with Star-delta switching function. Changeover contact with a changeover time of 50 ms Fixed timing function. The 031884/XTTR6A60S51B ETR 4 variant timing relay has been optimised for the measurement and monitoring relay as well as the safety relay. ETR4 timing relays offer maximum reliability in a broad range of applications. In fact, Eaton ETR4 timing relay is the ideal choice anywhere where reliable switching operations with extremely precise time delays are required. And on top of this, their slim design and large voltage range make them perfect for use by control panel, switchgear system, and controller manufacturers. Moreover, their range of functions, which can extend up to 10 functions in multi-function models, ensures that the most important timing flows can be covered with a single device, minimizing inventories even when applications vary.