Megger SR-98, Инструкция по эксплуатации

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CURRENT RELAY Test Screen
The CURRENT RELAY Test Screen is used for testing all overcurrent, voltage
controlled overcurrent, voltage restrained overcurrent and other AC current controlled
relays, including motor overload relays and small molded case circuit breakers. If
testing directional overcurrent, see DIRECTIONAL RELAY Test Screen.
The following are descriptions of each of the displayed values, features or functions in
the CURRENT RELAY Test Screen.
AC AMPERES ( 00.0% ): The value displayed is the measured output current from the
CURRENT MAINS output terminals. The (%) value displayed provides a reference
point for setting test current quickly and easily. The current can be adjusted in
approximate proportion to the % displayed. This is a big time saver when testing similar
relays with the same tap settings. However, there is an advantage that is different from
the old SR units, it's virtually linear. Let’s say you want to do multiple timing points on
the same relay. For example, you wish to test at 2, 4 and 6 times the tap rating of the
relay (this only works if you use the same CURRENT MAINS output tap for all tests).
When you set your test current for the first test point, let's say the % indication is 8 %.
To quickly adjust the test current for the next point (4 X), adjust the % indication to 16
%, go to the Momentary Mode, a give it a shot. The test current should be very close to
the desired test current. For the next point, adjust to 32 %. This does not account for
voltage drop in the test leads at high current values. Make sure you use the 6 mm test
leads. You might have to make a small adjustment to get the exact test current you
desire. But it does save time compared to the old hunt and peck, "jogging" method used
on the old style SR units. And, it reduces heat in the relay and the test set, since you're
not reapplying multiple shots of test current "hunting" for the proper setting. When
rotating the Control Knob, the % value changes up or down depending on the direction
of rotation.
AC VOLTS ( 00.0 V ):
The value displayed is the measured output voltage from the AC
AUX output terminals. The voltage value displayed in the ( 00.0 V ) is the estimated
output for the selected output terminal. The actual output voltage may vary slightly
depending on the actual load. This allows the operator to preset a voltage output
without turning the voltage on. When rotating the Control Knob, the voltage value
changes up or down depending on the direction of rotation