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If it has been 30 minutes or more since the device has received communication from the gateway has been received (Join Request success, Downlink from user, ACK response), then the device requests an Acknowledgement of its next Uplink. An ACK request without an ACK response is reported by status bit “RCE”. After 3 consecutive unsuccessful ACK requests, the actuator automatically switches to “Rejoin”. In this situation, the actuator switches to Safety Mode and Safety Value as specified by the user, and attempts to rejoin the a gateway. It sends a gateway Join Request at the frequency: 10 seconds, 10 seconds, 10 seconds, 2 minutes, then 1 hour until rejoined.
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