ProSoft Technology 5201-DFNT-104C - Manual (Page 64)

IEC-60870-5-104 Protocol Implementation 104C Version 3 ♦ ProLinx Gateway
Protocol Manual IEC 60870-5-104 Client (Firmware v3.xx)
Page 64 of 139 ProSoft Technology, Inc.
August 4, 2011
3.4.2 TESTFR Requests
Connections that are unused (but opened) may be periodically tested in both
directions by sending test messages (TESTFR=act), which are confirmed by the
receiving station sending TESTFR=con messages. The gateway can be
configured to periodically send this message using the following parameter:
In the example above, the gateway would send a TESTFR.ACT message 30
seconds after receiving the last message: