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When the device under test trips the timer will stop and the output will be switched off
automatically.
3.2
Primary Injection of an Over-Current Relay (PCU1-SP & LT)
Figure 3.2 PCU1-SP with over current device
3.2.1
Timer Mode
Internal start
3.2.2
Connections
Connect current output from loading
unit to desired input on device under
test.
Connect trip contact on the relay
under test to contact set 1 on the
control unit.
3.2.3
Test Procedure
Switch on the main supply switch.
Set the ammeter range switch to a
primary injection range (10%, 50% or
100%). Set the timer mode switch to
the off position.
Ensure that the output control is in the
zero position.
Check that connections are made as
above.
Press the output on push-button and
increase the current to the desired
level.
Press the output off push-button.
Select the internal start
position on the
timer mode switch.
Press the output on push-button.
When the device under test trips the
timer will stop and the output will be
switched off automatically.
3.2.4
Using Pulse Mode to Set the Current
When setting the current into the load pulse mode may be used to avoid injecting current for
long periods of time. Set the timer mode to pulse 0.2s and inject a series of pulses, adjusting
the output current until the desired current is set. Set the timer mode to internal start and then
press the on pushbutton.
