ITech IT6000C Series User Manual page 57

Power Supply Function
voltage remains within the voltage limit setting. CC priority mode is best suited
for use with batteries, power supplies, large charged capacitors, and loads that
are sensitive to current overshoots. It minimizes current overshoots during pro-
gramming, turn-on, and turn-off transitions and seamlessly transitions between
positive and negative currents.
In CC priority mode, the output current should be programmed to the desired
positive or negative value. A positive voltage limit range should also be set. The
voltage upper limit should always be set to a value that is greater than the actual
input voltage requirement of the external load. The following figure shows the
CC priority operating locus of the output. The area in the white quadrants shows
the output as a source (sourcing power). The area in the shaded quadrants
shows the output as a load (sinking power).
The heavy solid line illustrates the locus of possible operating points as a func-
tion of output. As shown by the vertical portion of the line, the output current re-
mains regulated at its programmed setting as long as the output voltage
remains within its limit setting. A CC (constant current) status flag indicates that
the output current is being regulated and the output voltage is within its limit
settings.
Note that when the output voltage reaches the upper limit, the unit no longer op-
erates in constant current mode and the output current is no longer held con-
stant. Instead, the unit will now regulate the output voltage at its voltage limit
setting.
As shown by the horizontal portion of the shaded quadrants, when the unit is
sinking power, the output current may continue to increase in the negative direc-
tion as more current is forced into the unit. This can happen when the instru-
ment is connected to an external device such as a battery, and its output
voltage is higher than the voltage limit setting of the instrument. Once the
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