Keysight Technologies N6900 Series, Руководство по эксплуатации и обслуживанию

Страница: 75 / 358

The noise specifications documented under Specifications 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 an aluminum or tantalum 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 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 supply to briefly 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.
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 power supply can be operated
with any output terminal ± 240 VDC including output voltage from ground.
The APS models 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.
Keysight N6900/N7900 Series Operating and Service Guide 75
2 Installing the Instrument