P14x
If the line is closed where a three-phase VT failure is present, the overcurrent detector will not operate and a VTS
block will be applied. Closing onto a three-phase fault will result in operation of the overcurrent detector and
prevent a VTS block being applied.
2.4
VTS IMPLEMENTATION
VTS is implemented in the SUPERVISION column of the relevant settings group.
The following settings are relevant for VT Supervision:
VTS Status: determines whether the VTS Operate output will be a blocking output or an alarm indication
●
only
VTS PickupThresh: determines the threshold at which the phase voltage detectors pick up
●
VTS Reset Mode: determines whether the Reset is to be manual or automatic
●
VTS Time delay: determines the operating time delay
●
●
VTS I> Inhibit: inhibits VTS operation in the case of a phase overcurrent fault
VTS I2> Inhibit: inhibits VTS operation in the case of a negative sequence overcurrent fault
●
VTS is only enabled during a live line condition (as indicated by the pole dead logic) to prevent operation under
dead system conditions.
2.5
VTS LOGIC
This logic will only be enabled during a live line condition (as indicated by the pole dead logic) to prevent operation
under dead system conditions (i.e. where no voltage will be present and the VTS I> Inhibit overcurrent element will
not be picked up).
P14xEd1-TM-EN-1
Chapter 15 - Supervision
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