Toshiba GRL150-100 Series Instruction Manual page 138

Operating time check for IDMT curve
The testing circuit is shown in Figure 6.5.1.5.
Single-phase
current
source
+
DC
power
−
supply
Start
Time
counter
Stop
OV
One of the inverse time characteristics can be set, and the output signal numbers of the IDMT
elements are as follows:
Fix the time characteristic to test by setting the scheme switch MOC1, MEF1 or MSE1 on the
"OC", "EF" or "SEF" screen.
Example: "Settings" sub-menu → "Protection" screen → "Group ∗ " screen → "OC" screen
The test procedure is as follows:
•
Enter the signal number to observe the operating time at the monitoring jack A as shown in
Section 6.5.1.
•
Apply a test current and measure the operating time. The magnitude of the test current should
be between 1.2 × I s to 20 × I s , where I s is the current setting.
•
Calculate the theoretical operating time using the characteristic equations shown in Section
2.3.1. Check that the measured operating time is within IEC 60255-3 class 5.
A
(∗): Connect the terminal number corresponding to the testing element. Refer to Table 3.2.1.
Figure 6.5.1.5 Testing IDMT
Element Signal No.
OC1-A 80
112
EF1
116
SEF1
⎯ ⎯
137
6 F 2 S 0 8 2 8
GRL150
TB1
∗
- (
)
∗
- (
)
A
Monitoring
jack
0V
TB2 -A9
-B9
E