Resistance Of Main Circuit - Siemens Fusesaver Installation And Operation Manual

3 Workshop testing
Every Fusesaver is inspected and tested at
the factory before dispatch. No further testing
by the end user is required. However, if the
user has a policy to do confirmation testing
before deployment, then the following
inspection and test regimes are possible
by suitably qualified personnel.
3.1 Dielectric test
To confirm the dielectric integrity
of the vacuum interrupter the user
can apply a 48 kV ac (50/60 Hz)
voltage across the open contacts
of the Fusesaver for 60 seconds.
Hazardous voltages are present during dielectric
testing.
Contact with an energized unit under test will
likely result in severe personal injury or death.
Dielectric testing should occur with a grounded
test cage to provide a physical barrier between the
technician and the equipment under test.
Fusesaver | Installation and operation manual
Note that vacuum interrupters can
experience self-extinguishing
momentary breakdowns under high
voltages. These momentary breakdowns
do not indicate a loss of vacuum or
failure of the test.
The vacuum interrupter may emit x-rays during
dielectric testing.
X-rays may be hazardous to your health.
Dielectric testing should be conducted within a solid
sheet metal cage made from ferrous material with a
minimum thickness of 0.06" (1.6 mm). The technician
should maintain a minimum 9.84 ft (3 m) distance to
the Fusesaver under test.

3.2 Resistance of main circuit

To confirm the integrity of the primary current path the user can measure the
resistance from terminal to terminal using a standard dc resistance meter with
a minimum 10 A capability.
The recommended resistance measurement by model is as follows:
Model type Low range
DC resistance µΩ
Standard range High range
<8070 <1350 <390
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