Toshiba GRT100 Series, Instruction Manual

Page: 116 / 270


115

6 F 2 S 0 7 8 9
Single-phase
current
source
A
TB 1 -1
- 2
GRT100
Monitoring
jack
A
0V
TB 4 - A16
- A17
E
DC
power
supply




DC
voltmeter


I a
Figure 6.5.1 Operating Current Value Test Circuit (Model 100s, 200s)
The output signal numbers of the DIF elements are as follows:
Element Signal number
DIF-A 44
DIF-B 45
DIF-C 46

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 operation at monitoring jack A and press
the
ENTER
key.

Apply a test current to A-phase current terminals and change the magnitude of the current
applied and measure the value at which the element DIF-A operates.
Check that the measured value is within 7% of the theoretical operating value.
Theoretical operating value = (CT secondary rated current)

(ik setting)
Percentage restraining characteristics
The percentage restraining characteristic is tested on the outflow current (I
out
) and infeed current
(I
in
) plane as shown in Figure 6.5.2.
The characteristic shown in Figure 6.5.2 is equivalent to the
one on the differential current (Id) and restraining current (Ir) plane shown in Figure 2.11.1.