Keysight E3633A, Руководство пользователя

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3 Front-Panel Operation
68 Keysight E3633A and E3634A User’s Guide
Output noise
Any noise picked up on the sense leads also appears at the output of the power
supply and may adversely affect the voltage load regulation. Twist the sense leads
to minimize external noise pickup and run them parallel and close to the load
leads. In 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 sense conductors.
Stability
Using remote sensing under certain combinations of load lead lengths and large
load capacitances may cause your application to form a filter, which becomes
part of the voltage feedback loop. The extra phase shift created by this filter can
degrade the power supply’s stability, resulting in poor transient response or loop
instability. In severe cases, it may cause oscillations. To minimize this possibility,
keep the load leads as short as possible and twist them together. As the sense
leads are part of the power supply’s programming feedback loop, accidental
open-connections of sense or load leads during remote sensing operation have
various unwanted effects. Provide secure and permanent connections.
Remote voltage sensing connections
Connections between the power supply sensing and output terminals should be
removed, and using shielded two-wire cable, the power supply sensing terminals
should be connected to the load as shown in Figure 3-2 . Do not use the shield as
one of the sensing conductors and the other end should be left unconnected.
Connect one end of the sensing lead shield to the chassis ground (
⊥
) only.
Opening a sensing lead causes the power supply output voltage to decrease at
the load leads. Observe polarity when connecting the sensing leads to the load.
For local voltage sensing connections, the (+) and (-) sense terminals must be
connected to the (+) and (-) output terminals respectively.