Citadel 2.0 - Instruction Manual - page:
122
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High-potential tests;
Vacuum-integrity test and insulation tests involve the use of high-voltage test
equipment.
The circuit breaker under test should be inside a suitable test barrier equipped with
warning lights.
Vacuum-integrity check;
A high-potential test is used to verify the vacuum integrity of the Citadel circuit breaker.
The test is conducted on the circuit breaker with its primary contacts in the Open
position.
Vacuum integrity test procedure
1.
Observe safety precautions listed in the danger and warning advisories.
2.
Know the test equipment and it operating practices. Only trained personnel
should attempt to perform High Potential tests.
3.
Construct a proper barrier perimeter around the test specimen and a warning
light system.
4.
Ground the frame of the circuit breaker. Ground each pole not under test.
5.
Apply test voltage of 27kV (refer to Table 17) across each “Open” pole for one
minute.
6.
If the pole sustains the test voltage for that period, its vacuum integrity has been
verified.
Note: Do not use dc high-potential testers incorporating half-wave rectification.
These devices produce high peak voltages. High peak voltages will produce
X-ray radiation. DC testers producing excessive peak voltages also show
erroneous readings of leakage current when testing vacuum circuit breakers.
High-potential test voltages
The voltages for high-potential tests are shown in Table 18 (page 123).
Note: This test includes not only the vacuum interrupter, but also the other
insulation components in parallel with the vacuum interrupter. These include
the post insulators and the insulating coupler, as well as the insulating push
rod assemblies and the vacuum interrupter supports. If these insulation
components are contaminated or defective, the test voltage will not be
sustained. If so, clean and / or replace the affected components and retest.
Vacuum interrupters may
emit X-ray radiation
WARNING
This can result in serious injury.
Keep personnel more than six feet away
from a circuit breaker under test.
M A I N T E N A N C E