Keysight Technologies N69100 Series, Руководство по эксплуатации и обслуживанию

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If the remote sense wires open during normal CV operation (with output current present), the change
in output voltage at the load will depend on the load current and the load wire resistances involved.
When the sense leads open, the unit automatically reverts to local sensing. The voltage at the
previous remote sense point (usually at the load) will change by an amount given by the following
equation:
Δ V= K(V
set
) - I
out
x (total resistance of load leads)
K = 1% for 1 kV models and 1.65% for 2 kV models
I
out
= positive when the unit sourcing current; negative when the unit is sinking current
Shorted sense leads are detected by the over-voltage protection function. This function results in the
output being disabled due to an over-voltage fault (OV). Reversed sense leads are detected by the
negative over-voltage protection function. This results in the output being disabled due to a negative
over-voltage fault (OV). Refer to
Additional Load Considerations for information about lead inductance
when using remote sensing with load capacitance and lead inductance.
Over-voltage Protection
Over-voltage protection (OVP) provides a configurable over-voltage protection based on sense lead
voltage. Having the OVP circuit monitor the sense lead voltage rather than the output terminal
voltage allows for more precise voltage monitoring directly at the load.
Note that due to the voltage drop in the load leads, the voltage at the output of the power supply
could be higher than the voltage being regulated at the load. The voltage at the output terminals of
the power supply should never exceed the unit's voltage rating.
Output Noise
Any noise picked up on the sense leads will appear at the output terminals and may adversely affect
CV load regulation. Twist the sense leads to minimize the pickup of external noise. In extremely noisy
environments it may be necessary to shield the sense leads. Ground the shield at the power supply
end only; do not use the shield as one of the sensing conductors.
The noise specifications documented in the specification tables apply at the output terminals when
using local sensing. However, voltage transients may be produced at the load by noise induced in the
leads or by load current transients acting on the inductance and resistance of the load lead. If it is
desirable to keep voltage transient levels to a minimum, place a high-voltage film capacitor, with an
approximate value of 10 microfarad per foot (30.5 cm) of load lead, right across the load.
Additional Load Considerations
Response Time with External Capacitor
When up-programming the output voltage with an external load capacitor, voltage response time may
be longer than with purely resistive loads since the power supply may enter constant current
operating mode, which adds additional response time. By setting the proper voltage slew rate when
using an external capacitor, it may be possible to prevent mode crossover into constant current.
Use the following formula to estimate the additional programming response time:
2 Installing the Instrument
68 Keysight N69100 Series Operating and Service Guide