Hioki IM3536, Инструкция по эксплуатации

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52
Setting Measurement Conditions (basic settings)
Constant current (CC) mode setting
Low Z high accuracy mode
(p. 56) is set to OFF
Low Z high accuracy mode
(p. 56) is set to ON
Constant current setting range
0.01 mA to 50.00 mA 0.01 mA to 100.00 mA
Constant current accuracy ±1%±10 µA
Output impedance 100
Ω
±10
Ω
10
Ω
±2
Ω
For some samples, you may not be able to perform constant-current measurement (measurement in con -
stant-current mode). In this case, the following error will be displayed:
Constant current measurement will not be performed. Change the constant-current value to a value that is
less than or equal to the value displayed for Iac.
(Example: Constant-current measurable range when measuring an L value of 1 mH at 1 kHz)
Sample impedance
Zm
becomes as follows:
Zm = Rm + jXm = 0 [
Ω
] - j6.28 [
Ω
] Xm = 2 π fL
The impedance Zm’ as seen from the instrument’s voltage generator is as follows:
Zm’ = Ro + Zm = 100 [
Ω
] - j6.28 [
Ω
] Ro:
Output resistance (100 [
Ω
])
Accordingly, the current
Im
across both leads of the sample is as follows:
Im =
Vo
|
Zm’
|
=
Vo
100.2 [
Ω
]
V o :
generator output
Since the instrument’s voltage generator output range is 10 [mV] to 5 [V] as per the above table, the con -
stant-voltage measurable range is Im = 0.10 [mA] to 49.9 [mA] based on the above formula.
When low Z high accuracy mode is enabled, the output resistance
Ro
will be 10 [Ω].
• When the measurement value is outside the guaranteed accuracy range, the following error massage ap -
pears at the top of the screen.
In this case, you should consider the following possible causes, and you should either change the mea -
surement signal level and measurement range while checking the accuracy assured ranges "Guaranteed
accuracy measurement level range" (p. 213), or you should consider the measured values as values for
reference.
• Measurement signal level is too low: Increase the test signal level.
• The current measurement range is inappropriate (when using the HOLD setting): set again in the AUTO
• range, or change the range by manual.