• The frequent operation counter limit is reached and new sequence is initiated.
The lockout is released when the recovery timer elapses
• The protection trip signal has been active longer than the time set with the Max
wait time parameter since the shot initiation
• The circuit breaker is closed manually during an auto-reclose sequence and the
manual close mode is FALSE.
9.4.4.6 Protection coordination controller
The PROT_CRD output is used for controlling the protection functions. In several
applications, such as fuse-saving applications involving down-stream fuses,
tripping and initiation of shot 1 should be fast (instantaneous or short-time
delayed). The tripping and initiation of shots 2, 3 and definite tripping time should
be delayed.
In this example, two overcurrent elements PHLPTOC and PHIPTOC are used.
PHIPTOC is given an instantaneous characteristic and PHLPTOC is given a time
delay.
The PROT_CRD output is activated, if the SHOT_PTR value is the same or higher
than the value defined with the Protection crd limit setting and all initialization
signals have been reset. The PROT_CRD output is reset under the following
conditions:
• If the cut-out time elapses
• If the reclaim time elapses and the AR function is ready for a new sequence
• If the AR function is in lockout or disabled, that is, if the value of the
Protection crd mode setting is "AR inoperative" or "AR inop, CB man".
The PROT_CRD output can also be controlled with the Protection crd mode
setting. The setting has the following modes:
• "no condition": the PROT_CRD output is controlled only with the Protection
crd limit setting
• "AR inoperative": the PROT_CRD output is active, if the AR function is
disabled or in the lockout state, or if the INHIBIT_RECL input is active
• "CB close manual": the PROT_CRD output is active for the reclaim time if the
circuit breaker has been manually closed, that is, the AR function has not
issued a close command
• "AR inop, CB man": both the modes "AR inoperative" and "CB close manual"
are effective
• "always": the PROT_CRD output is constantly active
Section 9 1YHT530004D05 D
Control functions
706 615 series
Technical Manual
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