PTT Default Settings
flexVUE
When PTT is enabled, the global pickup pages for Phase, Earth, SEF, and NPS are not displayed. Instead three additional pages for Setting, Pickup and Reset are added to the Protection Trip Settings sub menus for each of the four elements for each of the six trips if configured.
setVUE
When PTT is enabled, setting currents and multipliers for Phase/Earth/SEF/NPS are not displayed on the Protection Setting pages 1-3 and Protection Setting 4 is not displayed at all. An additional Threshold page appears preceding the Trip page for each element.
See the Protection Menu table in Appendix K.4.
Incorrect settings can cause unlimited auto reclose attempts when PTTs are enabled.
| NOTICE |
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HAZARD OF UNDESIRED BEHAVIOR OF APPLICATION
Attention must be paid to the fault current settings for
each Trip and it is strongly recommended to test these settings prior
to commissioning the controller.
Failure to follow these instructions can result in equipment damage.
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If auto reclose is on and
the Setting Current for a trip in a sequence is higher than for a
trip earlier in the sequence it is possible to get into a continuous
Trip – Sequence Reset cycle.
An example of
how this could happen is explained below.
Trip 1 Phase Setting Current = 100 A
Trip 2 Phase Setting Current = 300 A
A 200 A fault will cause Trip 1 but the ACR will reclose successfully
as the fault level is below the Trip 2 setting. As soon as the Sequence
Reset time expires,
Trip 1 will again become the active
trip. That will cause another Trip 1 followed by a sequence reset
and the cycle will continue.