Protection - DEMA 400 Series User Manual

4.3.2.7.1

Protection

It can be selected 'Active' or 'Passive'.According to the treshold situation, the protection is
activated in the active state and disabled in the passive state.
4.3.2.7.2 Start Value
The display shows how many times the nominal current value starts when the protection is
active. Selection is made in (0.05-35) In range.
4.3.2.7.3 Delay Type
The type of delay curve for protection is assigned from this option. These curves can be
selected from the Main Menu> Protection Settings> Protection and Reset Curves> Protection
and Reset Curves Table
4.3.2.7.4 Operate Delay
The operation delay is the value that determines the characteristic of the protection curve with
the delay type. If the delay type is selected as DMT, delay can have a value in the range of
(0.02 - 200) s. If the delay type is selected as one of the IDMT curves, the delay is expressed
by the term "TMS" and It can be adjusted between (0.025 – 5)
The TMS value is calculated based on several arguments such as features of the protected
facility and protection selectivity requirements.
4.3.2.7.5 TMS
The TMS value that determines the characteristic of the protection curve together with the
delay type. TMS setting; The delay type is activated when one of the curves except DMT is
selected. TMS is calculated based on several arguments such as features of the protected
facility, protection selectivity requirements. TMS value can be selected between (0,025-5)s
4.3.2.7.6 Reset Type
Negative Sequence Overcurrent Protection Display
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