Keysight U8001A, Руководство пользователя и сервисное руководство

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Service Guide 5
Keysight U8001A/U8002A User’s and Service Guide 61
Current monitoring resistor
To eliminate output current measurement error caused by the voltage drops in the
leads and connections, connect the current monitoring resistor (R
M
) between the
(–) output terminal and the load as a four-terminal device. Connect the current
monitoring leads inside the load-lead connections directly at the monitoring
points on the resistor element.
General measurement techniques
To achieve best results when measuring load regulation, peak to peak voltage,
and transient response time of the power supply, measuring devices must be
connected through the hole in the neck of the binding post at (A) while the load
resistor is plugged into the front of the output terminals at (B). A measurement
made across the load includes the impedance of the leads to the load. The
impedance of the load leads can easily be several orders of the magnitude greater
than the power supply impedance and thus invalidate the measurement. To avoid
mutual coupling effects, each measuring device must be connected directly to the
output terminals by separate pairs of leads.
Figure 5-3 General measurement