Pulse Loading Considerations; Capacitive Loads; Reverse Current Loading - Agilent Technologies E3610A Operating And Service Manual

Pulse Loading Considerations

The power supply will automatically cross over from constant-
voltage to constant-current operation in response to an
increase (over the preset limit) in the output current. Although
the preset limit may be set higher than the average output
current, high peak currents (as occur in pulse loading) may
exceed the preset current limit and cause crossover to occur.
If this crossover limiting is not desired, set the preset limit for
the peak requirement and not the average.

Capacitive Loads

An internal capacitor, across the output terminals of the
power supply, helps to supply high-current pulses of short
duration during constant voltage operation. Any capacitance
added externally will improve the pulse current capability,
but will decrease the safety provided by the current limiting
circuit. A high-current pulse may damage load components
before the average output current is Iarge enough to cause
the current limiting circuit to operate.

Reverse Current Loading

Active loads connected to the power supply may actually
deliver a reverse current to the power supply during a portion
of its operating cycle. An external source can not be allowed
to pump current into the supply without loss of regulation and
possible damage to the output capacitor. To avoid these
effects, it is necessary to preload the supply with a dummy
load resistor so that the power supply delivers current through
the entire operating cycle of the load devices.
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