NF FRA51602, Инструкция по эксплуатации

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4.2 Simple operation for the first use
4
-
7
FRA 51602
！
Warning

A large output may be generated if the control loop is broken, resulting in possible
damage to the equipment under test or risk of injury to the user. Ensure that an open
control loop does not occur even if the probe is disconnected from the instrument by
using an injection resistance. Secure the injection resistance firmly to ensure that it
remains in place.

If the injected signal level is too high, the generated output may be large enough to
damage the equipment under test or create a risk of injury to the user. Begin with a low
signal level and increase it gradually, with sufficient checking for safety.
Using the optional "
PA-001-0369 LOOP GAIN MEASUREMENT ADAPTER
" simplifies the
connection between the circuit under test and the instrument and reduces the possibility of incorrect wiring.
However, using the adapter restricts the voltage to ±42 V. For more information, refer to the instruction
manual of the " PA-001-0369 LOOP GAIN MEASUREMENT ADAPTER" .
Follow the procedure described below for instrument set-up and performing measurements.
1) Initialize the settings.
2) Press the
BASIC SETUP
key and change the settings if necessary. In most cases, loop gain
measurements can be performed without problem with the settings other than measurement amplitude
(AMPLITUDE) left unchanged.
[SWEEP LOWER] : Sweep frequency lower limit
[SWEEP UPPER] : Sweep frequency upper limit
[AMPLITUDE] : Measurement amplitude
Denoting the output voltage of the DC-DC converter that is being measured
as V, set the value to approximately V/50 or less. If the output voltages 5 V,
set the value to about 100 mVpk; for an output voltage of 400 V, set the
value to about 8 Vpk.
[INTEGRATION] : Number of integration rounds.
3) Press the
AC/DC ON
key on the front panel to turn the oscillator output on.
4) Press the
MEASURE DOWN
key on the front panel to perform a sweep measurement and wait until the
measurement is completed.
5) Turning the knob moves the marker on the measurement data. Search for the frequency at which the gain
is closest to 0 dB. The phase at that frequency is the phase margin. That frequency (the zero cross
frequency) is a measure of the control response speed of the circuit under test.