56
13. Press
PREV SCREEN
.
14. Press
the
INIT
Button. The current turns ON at the value set in Momentary
mode. The timer starts. Relay trips. Output turns OFF. Timer Stops. Trip LED
turns ON. The horn beeps (if the horn was turned on). Record trip time.
Instantaneous Pickup Test:
Connect the relay as described for the Pick Up Test above. If the relay has separate coil
and trip contacts for the Instantaneous Element, connect the appropriate
AC MAIN
OUTPUT
terminals to the instantaneous coil and the trip contacts to the
STOP/MONITOR
terminals.
1.
Using arrow key highlight
AC AMPERES.
2. With
MODE
set to
MOM.
(MOMENTARY), press the
INIT
button. The output
current should turn on for short pulse duration.
3.
Rotate Control Knob clockwise slightly, and press the
INIT
Button. Observe
current reading retained by ammeter. Continue this procedure until the
instantaneous element picks up.
4.
Read and record the Pick-up current. Return the current to zero.
DC Target and Seal In Test:
Many different types of relays use DC target and seal-in coils. DC targets and seal-in
coils are tested using the
DC Relay Test Screen
. See
DC
TARGET AND SEAL IN
test
procedure under
TIME DELAY OVERCURRENT DEVICES
.
Slope (Differential Characteristic) Test:
The
Slope (Differential Characteristic) Test
requires two SR-98’s operating in Master/
Slave mode, see SELECTION OF MASTER UNIT. Select one unit to be Slave unit. The
Master unit INIT button controls both the Master and Slave AC CURRENT MAIN
outputs. It also establishes the in-phase relationship between the two currents. When
choosing output taps, select the same tap for both units. For example, use the 45 Amp
output tap on both units. Note: Failure to use the same output taps will result in phase
shift error between the two currents.
From the
TEST MENU
Screen on both units, select
CURRENT RELAY
. The following
test screen should be displayed.
Summary of Contents for SR-98
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