Operation Principle - Hitachi Relion 650 Series Technical Manual

1MRK 511 557-UEN Rev. A
10.2.6

Operation principle

The Double point indication status times DPISTTIM function computes the status times of a double
point indication (DPI) by counting the times since the last status changeovers. The inputs for this
function are two boolean signals of a DPI. DPISTTIM function is intended for computing the idle
times (that is, time since the last open and close operations) of a switch.
The function interprets DPI input combinations as switch status according to
Table 68:
NO
0
0
1
1
Invalid input status combinations will generate an alarm or warning if applied for longer than a grace
period defined by TimeToAlm. ALMSTS directly indicates detection of an invalid input status.
CNTWRN indicates that an invalid condition has been detected even though the outputs show valid
time count values; it will be reset on a valid status transition.
The outputs provide the elapsed time from the last status changeover in the unit specified by
TimeScale (milliseconds, seconds, minutes, or hours). OPNTIME gives the time since the last closed
→ open transition; CLSDTIME gives the time since the last open → closed transition.
A rising edge (0 to 1 change) on the RSTTIMS input will reset both OPNTIME and CLSDTIME to 0.0.
The setting ModeStsCntSenErr controls the behavior of the internal counters and the outputs when
an invalid input status is detected for longer than TimeToAlm.
• If 'Reset to default' is selected then both counters will be reset to DefValue.
• If 'Freeze counters' is selected the counter outputs are frozen at the current values. However,
internally the counters continue as per the previous valid input status. If the input status is
restored to the same valid status, the outputs are re-activated to show the updated counter
values. If the input status is restored to the opposite valid status then the counters behave as
during a regular change between valid statuses.
• If 'Keep counting' is selected the counters continue counting the last valid status.
Table 69
Technical Manual
Input status combination in DPISTTIM
summarizes the behavior of the DPISTTIM function block.
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NC Status
0 Invalid
1 Open
0 Closed
1 Invalid
Section 10
General calculation
GUID-C6669B23-377E-4B59-86F4-F6CD8AC81AFF v1
Table 68.
105