Power Limit Operation - Keysight Technologies N6705C Operating And Service Manual

Power Limit Operation

To specify a power limit, press the Settings key to access the Source Settings window. Navigate to
and select the Advanced button.
For Keysight N6705 mainframes, the instrument will operate normally as long as the combined output
power is within the power rating of the mainframe If the combined power drawn from all of the outputs
exceeds the mainframe's power rating of 600 W, a power fault protection event will occur. This causes
ALL outputs to turn off and remain off until a protection clear command is given. A status bit (PF) will
indicate that a power fault protection event has occurred.
For Keysight N678xA SMU and N6783A-BAT/MFG, the power limit function does not apply.
For Keysight N675xA, and N676xA power modules, the power limit function limits the output power at
its programmed setting. A status bit (CP+) will indicate that the output is in power limit mode. When
the power drawn by the load is reduced below the power limit setting, the output returns to normal
operation. Note that these power modules contain an active down-programmer circuit, which is
limited to about 7 W continuous power. A status bit (CP-) will indicate that the output has reached the
negative limit.
For Keysight N673xB, N674xB, and N677xA power modules, the power limit function turns the output
off after a power limit persists for about 1 millisecond. A status bit (CP+) will indicate that the output
has been turned off by a power limit condition. To restore the output, you must first adjust the load so
that it draws less power. Then clear the protection function as previously explained. For these power
modules, it may be preferable to use the current or voltage setting to limit the output power so as to
avoid turning the output off.
If the power limit is left at the maximum rating, these power modules will not enable the
power limit protection. The power limit protection will only activate when the power limit
is set to a value less than the maximum rating of the power module and the output
power subsequently exceeds this limit setting
Keysight N6705C Operating and Service Guide
6 Advanced Source, Measurement, and Control
193