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menu list. The user simply selects what type of relay is to be tested and a test screen is
provided that displays all the necessary metering and functions needed to test that type of
relay. For example, the SR-98 can test single-phase impedance relays. The test screen for
a distance relay is shown below.
Screens shown have been slightly reduced in size (from actual) for printing purposes
Not only does the display screen show the metered values, but in this example, it also
display’s the OHMS value where the relay picks up (different formulas for calculating
OHMS are selectable using the OHM SELECT function button).
APPLICATIONS
The combination of single-phase AC voltage, AC current, with a variety of fixed output
frequencies and phase shift capability, DC voltage, and DC current, provides powerful
testing capabilities. For example, the AC Current output can provide 16.66 or 25 Hz, for
testing light rail transit system relays. In addition, the AC Current can also be
programmed to provide 2
nd
, 3
rd
and 5
th
harmonic currents, for testing harmonic restraint
elements in transformer differential relays.
The user simply selects from a menu screen for different testing applications. For
example see the TEST MENU below.
As can be seen, the SR-98 can test a wide selection of relay types. The phase shift
capability means that the unit can continuously adjust the phase angle relationship
Summary of Contents for SR-98
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