Megger SR-98, Инструкция по эксплуатации

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TEST APPLICATIONS
The SR-98 unit is designed for shop or field testing of protective relays, auxiliary relays,
molded case circuit breakers and overload coils. Other test applications include thermal
or magnetic motor overloads, in-line motor cutouts, relay coils, panel board ammeters
and voltmeters and ratioing current transformers. The independent Start and Stop
gates on the Timer provide the capability to measure the operating time of protective
relays, EHV to low voltage circuit breakers, trip circuits, contactors or other similar
switching devices.
WARNING: Do not use the test set for other applications not
specified above that could endanger the operator or the device under test. For
example, do not use the voltage output to ratio a potential transformer, since the
transformer may generate extra high voltages.
TEST PROCEDURES
The following test procedures are for specific types of relays, or families of relays. For
example, the following OVERCURRENT test procedure can apply to all electro-
mechanical , solid state and microprocessor overcurrent, voltage controlled overcurrent
and voltage restrained overcurrent relays. For directionally controlled overcurrent, there
is a separate test screen, since the directional element requires a phase shift between
the voltage and current elements. The IMPEDANCE relay test procedure applies to all
single-phase, and some three-phase, impedance relays. This would include not only
distance relays, but loss of excitation and other relays with an impedance characteristic.
TIME DELAY OVERCURRENT DEVICES
From the
TEST MENU Screen, select CURRENT RELAY . The following test screen
should be displayed.
Connect Relay Trip contacts to
STOP/MONITOR
gate.
Connect
AC CURRENT MAIN
to Current Coil.
Connect
DC AUX
output to relay (for solid state).
Connect
AC AUX
output to relay if AC controlled.
Note: If relay is solid state, or microprocessor-based, and requires a DC logic voltage
prior to applying test currents, connect the relay dc power terminals to the
DC AUX
terminals. With the arrow key, highlight the
DC VOLTS
and press the
DC
Button.