Keysight Technologies N6700, Руководство пользователя

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2 Installation
42 Keysight N6700 User’s Guide
Additional Load Considerations
Response Time with an External Capacitor
When programming with an external capacitor, voltage response time
may be longer than that for purely resistive loads. Use the following
formula to estimate the additional up-programming response time:
Response Time = (Added Output Capacitor)X(Change in Vout)
(Current Limit Setting)−(Load Current)
Note that programming into an external output capacitor may cause the
power system to briefly enter constant current or constant power
operating mode, which adds additional time to the estimation.
Positive and Negative Voltages
Either positive or negative voltages with respect to ground can be
obtained from the output by grounding (or "commoning") one of the
output terminals. Always use two wires to connect the load to the output
regardless of where or how the system is grounded. The instrument can
be operated with any output terminal
±
240 VDC including output
voltage from ground.
NOTE
Keysight Models N678xA SMU are optimized for grounding the negative
output terminal. Grounding the positive terminal may result in increased
current measurement noise and a reduction in current measurement
accuracy.
Protecting Sensitive Loads from AC Power Switching Transients
NOTE
This only applies if you are connecting loads that are highly sensitive to
voltage or current transients to the output of the power system. If your
load is connected directly to the output of the power system and is not
connected to chassis ground in any way, you do not need to worry about
AC power switching transients appearing at the output of the power
system.
Operating the AC line switch can inject common mode current spikes
into the DC output leads, resulting in voltage spikes that may damage
loads that are highly sensitive to voltage or current transients. Note that
any electronic device meeting international standards for EMI
compliance is likely to generate similar current spikes. This situation
arises from the presence of EMI filters at both the AC input and the DC
output. These filters typically include common mode capacitors
connected to the chassis of the power system. Since the AC input has an
earth ground, any load that is also earth-grounded provides a possible
return path for common mode currents.
The following figure illustrates a typical situation where a load that might
otherwise be floating becomes grounded, thereby providing a return