9.1 Test procedures.
This section includes guidelines for the proper testing of a High-speed DC Circuit Breaker.
9.1.1 To determine the release threshold.
Use the Auto Mode to accurately determine and check a known over-current release Imax/I
ds
.
If the value of the over-current release Imax/I
ds
is not known, the operator can use the Quicktest Mode first. The over-
current release observed during this test is automatically used as a reference in Auto Mode.
In Auto Mode, the BALTO System generates current with a fast rising slope up to a given level of the I
ds
threshold. The
current increase then continues with 200 A/s, up to a level slightly above the I
ds
threshold.
Using this procedure, the requirements of the IEC standard are met.
In case of a deviation - or if an adjustment of the release threshold is necessary - adjust the High-speed DC Circuit
Breaker and repeat the procedure until a stable release value - according to the allowed tolerance drawn up by the
manufacturer - is obtained.
9.1.2 To determine the opening time.
To determine the opening time, the Opening Time Test under Manual Mode can be used. This test determines the
mechanical response time of the High-speed DC Circuit Breaker.
The parameters of this test are adjusted automatically based on the results obtained in Auto Mode.
The value of this opening time should be reflected in the property sheet of the test object as specified by the
manufacturer.
9.1.3 To determine the voltage drop.
For this measurement, use the test labelled ‘mV’.
The expected value, and the conditions under which the test must be performed, should be included in the property
sheet of the test object as specified by the manufacturer.
For High-speed DC Circuit Breakers on rolling stock, it is advised to additionally perform the following tests:
The manual closing/opening time test (Reaction Time Tests) and the proper functioning of the auxiliary contacts
(I_Max No - NC).
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Operation
