Protection Functions
PRS-7367 161
3.32.3 Application Scope
Mechanical protection is based on fault information characterized by mechanical binary inputs,
such as temperature, oil speed, pressure and so on. The mechanical protection includes gas
protection, pressure protection, temperature protection, oil level protection and so on.
3.32.4 Settings
In the following table, i is the protection stage number, it can be set according to the requirements.
Table 3.32-3 MP settings
Enable: The output of MP is MP_Op;
Disable: The output of MP is MP_Alm
3.33 General function block
3.33.1 IDMT curves for over quantity protection
The inverse-time modes, the operation time depends on the momentary value of the quantity
(such as fault current or voltage): the higher the quantity, the faster the operation time. The
operation time calculation starts immediately when the quantity exceeds the set Start value.
User can select the operating characteristic from various inverse-time characteristic curves by
setting Curve_Type (=0,1, 2, 3, 4 or 5), and parameters of available characteristics for selection
are listed in the following table.
Table 3.33-1 Curve parameters for IEC IDMT curves
Programmable user-defined
If the Curve_Type = 1, 2, 3, 4, the Curve type is IEC Inverse-time mode and the time duration can
be calculated according to the formula:
s
()
( / ) 1
p
A
t B k
GG
  
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