ABB RELION REF615R, Техническое руководство

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12.2.2 Reset in inverse-time modes
The user can select the reset characteristics by using the Type of reset curve setting.
Table 439: Values for reset mode
Setting name Possible values
Type of reset curve 1=Immediate
2=Def time reset
3=Inverse reset
Immediate reset
If the Type of reset curve setting in a drop-off case is selected as "Immediate", the inverse
timer resets immediately.
Definite time reset
The definite type of reset in the inverse-time mode can be achieved by setting the Type of
reset curve parameter to “Def time reset”. As a result, the trip inverse-time counter is
frozen for the time determined with the Reset delay time setting after the current drops
below the set Pickup value , including hysteresis.The integral sum of the inverse-time
counter is reset, if another pickup does not occur during the reset delay.
If the Type of reset curve setting is selected as “Def time reset”, the current
level has no influence on the reset characteristic.
Inverse reset
Inverse reset curves are available only for ANSI and user-programmable
curves. If you use other curve types, immediate reset occurs.
Standard delayed inverse reset
The reset characteristic required in ANSI (IEEE) inverse-time modes is provided by
setting the
Type of reset curve parameter to “Inverse reset”. In this mode, the time delay
for reset is given with the following formula using the coefficient D, which has its values
defined in the table below.
t s
D
I
I
k [ ]
=
>





 −














⋅
2
1
A060817 V3 EN
(Equation 37)
1MRS240050-IB C
Section 12
General function block features
REF615R 595
Technical Manual