Hioki 3522-50, Инструкция по эксплуатации

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5.7 Supplying DC Bias
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5.7.2 How to Supply a DC Bias Current
CAUTION
In order to avoid electric shock accident, be absolutely sure not to
touch the test terminals while the DC bias is being supplied to them.
Use the 9269 at more 100.1Hz or more with the EXT DC bias of the
3522-50 switched off. Useing the 9268 at less than 100Hz or with the
EXT DC bias switched on may result in abnormal measurements or
damage to the unit.
Do not short circuit between the clips of the test probes with the DC
bias still being supplied. Doing so may damage the probes or cause
a short circuit accident.
When measuring the element whose DC resistance is high (incl. open
state), a high voltage occurred on the H side may cause damage on the
main unit.
Capacitor
C
HC
↑
Z
Choke coil
CH
＋
−
3522-50
＋
−
DC current
source
Sample to be tested
L
POT
L
CUR
H
POT
H
CUR
C
HP
DC Bias Current Circuit
To supply a DC bias, use the optional 9269 DC BIAS CURRENT UNIT
(Maximum input current DC2 A).
For details on using the 9269, refer to the Instruction Manual of the 9269.
(Depending on the test frequency, test signal level, and test range, the 9269
cannot be used.)
Use the 9269 at more 100.1Hz or more with the EXT DC bias of the 3522-
50 switched off.
If the 9269 is not used, refer to the followings.
To supply a DC bias current to a transformer or a choke coil or the like,
construct an external bias circuit as follows.
Connect the sample to the measuring probe and then gradually raise the
voltage of the DC source to the specified DC bias level. To disconnect the
sample, gradually reduce the voltage of the DC source until the DC bias
supplied to the sample is decreased to zero. You may disconnect the sample
after this is achieved.
A Hcur side capacitor must have a small enough impedance (i.e. a large
enough capacitance) relative to the output resistance (50
Ω
) while a Hpot
capacitor must have a small enough impedance to the input resistance (10k Ω ).