Toshiba GR200 Series - 2.19.2 Characteristic and setting; 2.19.3 Miscellaneous functions; (i) Harmonic detection function; (ii) Block operation of CTF for BCD

6F2S1914 (0.49)
GRL200 (Soft 033 & 037)
- 288 -
2.19.2 Characteristic and setting
The hatched area of Figure 2.19-2 illustrates the BCD characteristic; the BCD function will
operate when the positive sequence current (I1) is larger than 0.04×In, the negative sequence
current (I2) is larger than 0.01×In, and the ratio |I
2
/I
1
| is higher than setting [BCD].
Figure 2.19-2 Characteristic of BCD
2.19.3 Miscellaneous functions
(i) Harmonic detection function
The operation of BCD can be blocked when the IED detects 2
nd
harmonic caused by the
phenomenon of magnetizing inrush current when a transformer is energized. To block the
operation of the BCD function during the occurrence of the harmonic, set scheme switch [BCD-
2fBlk] Block.
(ii) Block operation of CTF for BCD
The operation of the BCD function can be blocked by the current transformer failure (CTF)
function using a scheme switch. Block is set for scheme switch [BCD-CTFBlk] if the user wishes
to disable the operation of the BCD function when a current transformer failure occurs.
I
1
I
2
0.01×In
0.04×In
o














  




  
&
BCD