135
Unbalance protection for capacitor banks
(TOCC)
&KDSWHU
&XUUHQW
rent of stage IHigh is low compared to the earth fault current in the system. The current
stage I>Low is normally set to give alarm at 50% of the set operate current of stage
I>High.
The calculation of settings for the unbalance protection function must take into consid-
eration how the capacitor bank is built up and it is often made by aids of a computer
program.
6HWWLQJRIUHOD\RSHUDWLQJFXUUHQWV
If Is is the primary setting operating value of the function, then the secondary setting
current (Is
SEC
) is:
(Equation 61)
where I
SEC
is the secondary rated current of the main CT and I
PRIM
is the primary rated
current of the main CT.
The relay setting value is given in percentage of the secondary base current value, I
5b
,
associated to the current transformer input I5. The value for I>Low and I>High is given
from the formula:
(Equation 62)
Is
SEC
I
S EC
I
PRIM
--------------
Is
⋅
=
I
set
Is
SEC
I
5b
--------------
100
⋅
=
Содержание REO 517
Страница 10: ... RQWHQWV ...
Страница 16: ...6 Introduction to the application manual KDSWHU QWURGXFWLRQ ...
Страница 64: ...54 Blocking of signals during test KDSWHU RPPRQ IXQFWLRQV ...
Страница 88: ...78 Scheme communication logic ZCOM KDSWHU LQH LPSHGDQFH ...
Страница 100: ...90 Time delayed phase and residual overcurrent protection TOC1 KDSWHU XUUHQW Equation 36 Iset IsSEC I1b 100 ...
Страница 146: ...136 Unbalance protection for capacitor banks TOCC KDSWHU XUUHQW ...
Страница 166: ...156 Dead line detection DLD KDSWHU 3RZHU V VWHP VXSHUYLVLRQ ...
Страница 171: ...161 About this chapter KDSWHU RQWURO KDSWHU RQWURO ERXW WKLV FKDSWHU This chapter describes the control functions ...
Страница 293: ...283 About this chapter KDSWHU RJLF KDSWHU RJLF ERXW WKLV FKDSWHU This chapter describes the logic functions ...
Страница 378: ...368 Monitoring of DC analog measurements KDSWHU 0RQLWRULQJ ...
Страница 379: ...369 About this chapter KDSWHU 0HWHULQJ KDSWHU 0HWHULQJ ERXW WKLV FKDSWHU This chapter describes the metering functions ...
Страница 384: ...374 Pulse counter logic PC KDSWHU 0HWHULQJ ...
Страница 412: ...402 Serial communication modules SCM KDSWHU DWD FRPPXQLFDWLRQ ...
Страница 440: ...430 LED indication module KDSWHU DUGZDUH PRGXOHV ...