44
SYNC (Synchronizing) RELAY:
The SYNCH RELAY Test Screen is used to test synchronizing and sync check relays. It
may also be used to test reverse phase, or phase sequence voltage relays, which can
be tested using an Open-Delta test potential (see
Testing Phase Sequence
Undervoltage Relays
). The two voltage sources used to test synchronizing type relays
are the
230 V / 4 A
CURRENT MAIN
output terminal, with common, and the
AC AUX,
300 V / 0.25 A
output terminals. The measured voltages are labeled
(M)
for the
230 V
CURRENT MAIN
and
(AUX)
for the
AC AUX
output. The phase angle between the two
voltages is displayed as
φ
Vm lags V
, where
Vm
is the
(M)
output and the other
voltage
V
is from the
AC AUX
output.
Testing Synchronizing Relays:
From the
TEST MENU
Screen, select
SYNC RELAY
. The following test screen should
be displayed.
Connect Relay Closing contacts to
STOP/MONITOR
gate.
Connect the
230 V / 4 A
,
AC CURRENT MAIN
to the relay potential coil or input
(normally associated with the bus). Consider connecting the
AC AUX
output as the
leading voltage, since the voltage from the
MAIN
lags the voltage from the
AC AUX
.
Connect
AC AUX
output terminals to the other relay potential coil or input (normally
associated with the line or generator).
Connect
DC AUX
output to relay (for solid state or microprocessor-based).
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.
Summary of Contents for SR-98
Page 93: ...87...
