ProSoft Technology 5201-MNET-101S - Manual (Page 112)

Reference IEC-101 Slave ♦ ProLinx Communication Gateway
Protocol Manual IEC 60870-5-101 v3 Slave (Firmware version 3.xx)
Page 112 of 159 ProSoft Technology, Inc.
August 6, 2010
The following illustration shows how these parameters are implemented:
If a database bit address (1 to 64000) is present, the application may consider
the point with an invalid flag if the previous logic checks the IV bit as 1 during
consecutive IV Check Delay scans. The IV bits would have to be reset to 0 to set
the point to valid state.
The IV DB bit defined for each point can be unique, or many points may share
the same bit. The last case could be used when the points on an I/O gateway are
to be considered as one set. In this case only a single bit is required. For a point
that is the result of a computation, the valid quality state could be set for each
point individually.