GE BUS1000, Instructions Manual

Page: 37 / 129

7. ACCEPTANCE TESTS
GEK-98514B BUS1000 Busbar Protection 7-1
7. 7. 7. 7. ACCEPTANCE TESTS ACCEPTANCE TESTS ACCEPTANCE TESTS ACCEPTANCE TESTS
7.1. VISUAL INSPECTION
Check that the model or models indicated in the plates match the data given in the order. Unpack the
equipment and check there are no broken parts and no signs that the system has suffered any damage
during transportation.
7.2. ELECTRIC TEST
General Considerations on the Power Supply Network and the Measuring Equipment
The bus protection equipment has been calibrated in the factory using a 50 and 60 Hz network with a
minimum content of harmonics. In order to achieve consistent results, the tests must be carried out using a
power supply network whose wave shape does not contain harmonics.
The dc auxiliary infeed voltage used for tests must not be obtained with rectified a.c. because if this power
supply is not properly smooth, it is possible the measuring units do not operate correctly due to possible
voltage drops in the power source. Zener diodes, for example, may stop conducting because of power
supply voltage drops. As general rule, the dc power supply must not have a ripple higher than 5%.
The ammeters and chronometers used must be calibrated and their precision must be better than that of the
relay. The power supply network used in the tests must remain stable, mainly in the levels near the operation
thresholds and during the whole operation time of the relay.
It is important to point out that the accuracy with which the test is performed depends on the network and on
the instruments used. Functional tests performed with unsuitable power supply network and instruments are
useful to check that the relay operates properly and therefore its operating characteristics are verified in an
approximate manner. However, if the relay would be calibrated in these conditions, its operational
characteristics would be outside the tolerance range values.
7.3. STABILIZATION RESISTORS TEST
−
Check the value in Ohms of the stabilization resistor for every phase.
−
Adjust the resistors “correderas" to obtain the resistance value calculated for the operation, and check the
value in Ohms once the "correderas" bolts have been screwed.
7.4. AUXILIARY CURRENT TRANSFORMERS TEST
−
Check the transformation ratio in the different taps, according to the model.
−
Apply 300 Va.c. volts to the transformer secondary, with the primary opened and check that the current
consumption ranges between 30 and 60 miliamperes.