Toshiba GRT100 Series Instruction Manual page 118

 Press 4 (= Logic circuit) on the "Test" sub-menu screen to display the "Logic circuit"
screen.
 Enter a signal number 44 to observe the DIF-A output at monitoring jack A and press the
ENTER key.
 Apply an infeed current to terminal TB1-1 and -2.
When the infeed current applied is larger than the setting of ik (pu) and smaller than
kp(2+p )/2 + ik(2-p
1
When the infeed current applied is larger than kp(2+ p
DF2 is checked.
Note: When the default settings are applied, the critical infeed current which
 Apply an outflow current of the same magnitude and counterphase with the infeed current
to terminal TB1-9 and 10.
 Decrease the out flow current in magnitude and measure the values at which the element
operates.
 Check that the measured values are within 7% of the theoretical values.
For characteristic DF1, the theoretical outflow current is given by the following equation:
I = (2p )(I
out in
1
where, p = slope setting of DF1
1
ik = minimum operating current setting
When the default settings are applied, I
For characteristic DF2, the theoretical outflow current is given by the following equation.
I = [(2p )I
out 2 in
where, p = slope setting of DF2
2
kp = break point of DF1 and DF2
When the default settings are applied, I
Operating time
The testing circuit is shown in Figure 6.5.4.
)/4 (pu), characteristic DF1 is checked.
1
determines DF1 checking or DF2 checking is 1.56×(CT secondary
rated current).
ik)/(2+p
) (pu)
1
= [(I
out
(2p  p
)ik + 2(p )kp]/(2+ p
1 2 1
= 0.43× (CT secondary rated current).
out
 117 
)/2 + ik(2- p
1 1
0.3) / 3]× (CT secondary rated current).
in
) (pu)
2
6 F 2 S 0 7 8 9
)/4 (pu), characteristic