20
Effective January 2017
NOVA
®
15i, NOVA 27i, and NOVA 38i; Three-phase
microprocessor-controlled; installation and operation
instructions (S280-43-1)
Instructional Literature
IL0104001E
High-potential withstand testing
Use the following procedures to perform high-potential withstand
tests at 75% of the rated low-frequency withstand voltage for 60
seconds. See Table 8 for test voltages and Figure 20 for test
connection diagrams.
Test results for NOVA i reclosers equipped with the internal
voltage sensing option will be influenced by the source-to-ground
connected sensing resistor, especially if dc high-potential testing is
performed.
TEST 3
1. Open the recloser contacts.
2. Ground the recloser.
3. Connect and ground terminals 1, 3, and 5 (see Figure 9).
4. Connect terminals 2, 4, and 6.
5. Apply proper test voltage to terminals 2, 4, and 6.
6. The recloser should withstand the test voltage for 60 seconds.
7. Reverse the connections: ground terminals 2, 4, and 6.
8. Apply test voltage to terminals 1, 3, and 5 for 60 seconds.
9. The recloser should withstand the test voltage for 60 seconds.
TEST 1
1. Close the recloser contacts.
2. Ground the recloser.
3. Connect terminals 2, 4, and 6 (see Figure 9) together.
4. Apply proper test voltage (see Table 8) to terminals 2, 4, and 6.
5. The recloser should withstand the test voltage for 60 seconds.
TEST 2
1. Close the recloser contacts.
2. Ground the recloser.
3. Ground Phase A (terminal 2) and Phase C (terminal 6).
4. Apply proper test voltage to Phase B (terminal 3).
5. The recloser should withstand the test voltage for 60 seconds.
Hazardous voltage. The switchgear and high voltage transformer must be
in a test cage or similar protective device to prevent accidental contact
with the high voltage parts. Solidly ground all equipment. Failure to
comply can result in death, severe personal injury, and equipment
damage.
WARNING
Radiation. At voltages up to the specified test voltages, the radiation
emitted by the vacuum interrupter is negligible. However, above these
voltages, radiation injurious to personnel can be emitted. See Service
Information S280-90-1, Vacuum Interrupter Withstand Test Voltage
Ratings Information for further information.
WARNING
1
3
5
2
4
6
ac
TEST 1
Phase to ground
1
3
5
2
4
6
ac
TEST 2
Phase to phase
1
3
5
2
4
6
ac
Open contact
1
3
5
2
4
6
ac
Open contact
TEST 3
Figure 20.
Connection diagrams for high-potential withstand testing.
*
Approximately 0.53mA additional leakage current with internal
voltage sensors.
†
†
Approximately 0.32mA additional leakage current with internal
voltage sensors.
* *
Approximately 0.37mA additional leakage current with internal
voltage sensors.
Table 8
NOVA i Recloser withstand test voltage ratings information.
75% of Rated Low-Frequency
Withstand Voltage
(1 minute dry) (kV rms)
Description ac
dc
NOVA 15i
37.5
53.0
*
NOVA 27i
45.0
63.5
NOVA 38i
52.5
74.2
**
