42
Ensure that the output control is in the zero position.
Press the output ON push-button and increase the output current to the desired level.
Press 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
Primary Injection of an Over-Current Relay
Figure 3.2 CU-Ps 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
figure 3.2.
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.