Vanguard RFD-200 S2 - Manual (Page 19)

REV 2 RFD-200 S2 USER’S MANUAL
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3.3 Using the RFD-200 S2’s Timer to Test Circuit Breaker Response Time
Use the steps below to use the RFD-200 S2’s timer to measure the opening time of a circuit
breaker. The timer will start when the RFD-200 S2 detects the voltage being applied to the
circuit breaker trip coil. The timer will stop when the RFD-200 S2 detects that the circuit
breaker contact has opened.
a. Connect the [TIMER START] input to the circuit breaker coil terminals as shown in
Figure 3.
b. Select WET for the [TIMER START] input. The timer will start when the trip coil is
energized.
c. Connect the
[TIMER STOP]
input to the circuit breaker dry contact as shown in Figure
3.
d. Select DRY for the
[TIMER STOP]
input. The timer will stop when the circuit breaker
contact is opened.
e. Turn the [VOLTAGE CONTROL] knob counter-clockwise to zero (until it can no
longer be turned).
f. Select START-ON from the control mode area.
g. Open the circuit breaker. The RFD-200 S2’s timer will start when the circuit breaker coil
voltage is detected, and it will stop when the circuit breaker contact has opened.
h. The [TEST COMPLETE] LED will be illuminated when the test has finished. The time
will be displayed on the LCD screen in milliseconds and cycles.