The Sentry series from ABB includes safety relays ranging from basic models for simple safety applications and safety output extensions to highly flexible universal models with timer functions. Both manual and automatic reset are selectable via a switch on the front of the relays. The multi-reset function allows a maximum of ten safety relays to be reset with just one reset switch, simplifying reset procedures and connections and minimizing downtime. It also reduces the number of reset switches required, cable length, space requirements, installation time and, in some applications, the number of safety relays required. The safety relays are connected to each other and communicate via the reset connection. To reset several safety relays simultaneously, all safety circuits must be closed and all safety inputs must be accepted. Four main types of safety relay are available. Removable terminals reduce connection and replacement times. Outputs up to 6 A save the use of additional contactors. 3-color LEDs provide more status indication and simplify troubleshooting. Models with integrated display offer preset configurations and extensive fault information to minimize downtime. The timer functions can be set from 0 to 999 s with an accuracy of better than 1 %.