The 3WL9111-0AT44-0AA0 circuit breaker test device is used to
test the functions of the SENTRON 3WL low-voltage circuit breaker.
For the ETU15B, ETU25B, ETU27B, ETU45B, ETU55B and
ETU76B overcurrent releases of the 3WL circuit breaker, the circuit
breaker test device can be used to:
• Measure the operating currents and tripping times.
• Check the protection functions for the three phases and
the neutral conductor.
• Verify the function of the tripping solenoid.
• Check the function of the ground-fault protection.
• Measure the opening time of the circuit breaker and to
• Check the trip causes.
The circuit breaker test device generates either a one or two-phase
test voltage that reproduces the output signal of the current sensors
(Rogowski coils). The test voltage is fed into the incoming circuit of
the current measuring device (L1, L2, L3 and N) as either onephase
or two-phase (180° phase shift) voltage. The level of the
simulated test current is infinitely variable from zero to 150 kA in
Note: A two-phase test voltage infeed is required if the ground fault
release is not deactivated.
The setting range of the test current allows the characteristic curves
of all electronic overcurrent releases (ETU = Electronic Trip Unit) to
be checked. Therefore, the device does not normally require the
settings of the electronic overcurrent releases to be altered.
This circuit breaker test device is equipped with a display for setting
the required test current.
The circuit breaker test device takes the frequency dependency of
the test voltage of 50 and 60 Hz appliances into consideration. The
tripping and opening times are also indicated on the test device
display. For carrying out the tests, the overcurrent release can either
be mounted in the circuit breaker or, in special cases, it can be
tested separately. However, the release has to be mounted in the
circuit breaker for testing the tripping solenoid and the opening
times of the circuit breaker.