Megger SR-98, Инструкция по эксплуатации

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POWER RELAY:
The POWER RELAY Test Screen is used to test single-phase over power, reverse
power or synchronous motor loss of excitation relays. In addition, some three-phase
relays may be tested with the potential coils paralleled and current coils in series. From
the
TEST MENU
Screen, select
POWER RELAY
. The following test screen should be
displayed.
Connect Relay Trip contacts to STOP/MONITOR gate.
Connect AC CURRENT MAIN to the relay current coil or input (note polarity).
Connect
DC AUX
output to relay (for solid state or microprocessor-based).
Connect
AC AUX
output terminals to the relay potential coil or input (note polarity).
Note: If relay is solid state, or microprocessor-based, and requires a DC logic voltage
prior to applying test, connect the relay dc power terminals to the
DC AUX
terminals.
With the arrow key, highlight the
DC VOLTS
and press the
DC
Button. Increase the DC
voltage output by rotating the Control Knob until proper logic voltage is applied.
Power Directional Element Pick Up or “Sensitivity” Test:
1. Press
the
WATT SELECT
Button and select the desired formula for calculating
the WATTS pick up value. The
WATTS
displayed is the calculated value based
on the displayed formula. The three formulas available are
(W)
= (VI*COS
∅
),
(W*1.7)
= (Watts * Square Root 3) and
(W/1.7)
= (Watts/Square Root 3). These
three formulas cover virtually all single-phase power, and some three-phase
power and loss of field relays.
2.
Using the arrow key, highlight the
AC VOLTS
. Press the
AC AUX
button to turn
the AC Volts on.
3.
Rotate Control Knob and increase AC Voltage output to the desired test voltage.
4. Using the arrow key, highlight the
AC AMPERES
.
5. With
MODE SELECT
set to
MAINT.
(MAINTAIN), press the
INIT
button.