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What type of tests are performed on accessories that are used on UL489 listed circuit breakers?

Tests on accessories
Shunt trip and undervoltage trip
These devices are submitted to temperature, overvoltage, operation, endurance and dielectric tests.
Overvoltage test
The device must be capable of withstanding 110% of its rated voltage continuously
without damage (this test does not apply to a shunt trip with an ``a`` contact
connected in series).
Operation
The shunt trip must operate at 75% of its rated voltage (except shunt trip devices
for use with ground-fault protection shall operate at 55%).
The undervoltage trip must trip the circuit breaker when the voltage is less than
35% and may trip the circuit breaker between 35 and 70% of its rated voltage and
shall pick-up and seal when the voltage is at 85% or more of its rated voltage.
Endurance
The device must be capable of performing successfully for 10% of the number of
``with current`` operations of the circuit breaker.
Auxiliary and alarm switches
Auxiliary and alarm switches must be submitted to temperature, overload, endurance
and dielectric tests.
Overload test
The test consists of fifty operations making and breaking 150% of rated current at
rated voltage, with a 75-80% power factor in ac and non-inductive load in dc.
Endurance
The switch must make and break its rated current at rated voltage, with a 75-80%
power factor in ac, and non-inductive load in dc for 100% of the number of
operations ``with current`` for auxiliary switches, and 10% of this number for alarm
switches.
Motor operator
The motor operator shall perform the number of ``without current`` operations
indicated for the circuit breaker endurance tests. The first 25 operations shall be
conducted at 85% of the motor operator voltage rating.
The circuit breaker is to be tripped during these tests.
The next 25 operations shall be conducted at 110% of the motor operator voltage
rating. The balance shall be completed at rated voltage without tripping the circuit
breaker.


CTA-ID : 9160
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