Table 2-5. Constant Current (CC) Tests (continued)
| Action | Normal Result |
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CC Source Effect
This test measures the change in output current resulting from a change in ac line voltage from its minimum to its maximum value within the line voltage specifications. It is recommended that you use averaged readings for Steps 6 and 8 of this test (see "Averaging AC Measurements" at the end of this chapter) .
1
2
3
4
5
6
7
8
9
Turn off the power supply and connect the ac power input through a
Set the transformer to the nominal ac line voltage. Connect the DVM across the current monitoring resistor (see Fig.
Turn on the power supply and program the current to its
Set the Electronic Load to CV mode and its voltage to full scale.
Adjust the transformer to decrease the ac input voltage to the
Observe the DVM reading. Divide this voltage by the resistance of the current monitoring resistor to obtain the output current. Record the result.
Adjust the transformer to increase the ac input voltage to the
Observe the DVM reading. Divide this voltage by the resistance of the current monitoring resistor to obtain the output current. Record the result.
Check the test result.
The power supply output current is full scale and its CC annunciator is on. If not, reduce the Electronic Load voltage slightly until the annunciator comes on.
You may want to use an averaged reading for this measurement.
You may want to use an averaged reading for this measurement.
The difference between the current readings found in Step 6 and Step 8 is within the specified current Source Effect limits.
