5-9
IM 701240-01E
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App
Index
Horizontal and Vertical Axes
Input Coupling and Frequency Characteristics
The frequency characteristics when AC or DC is specified are shown below.
Note that low-frequency signals and signal components are not acquired if AC is
selected as indicated in the figure below.
0 dB
–3 dB
–3 dB point*
Attenuation
0 dB
–3 dB
–3 dB point*
Attenuation
The lower frequency –3 dB
point when using AC coupling*
Input frequency
Input frequency
When “AC” is selected
When “DC” is selected
* The value varies for each input module. For details, see section 18.12.
Notes for 701261, 701262, 701265, 701275, and 701280
• If the input coupling is changed from TC to DC or DC to TC while waveform
acquisition is stopped on the 701261 (UNIVERSAL), 701262 (UNIVERSAL (AAF)), or
701265 (TEMP/HPV), the waveforms are no longer drawn. If you set the input
coupling to the original setting, the waveforms are redrawn.
• If the input coupling is changed from ACCL to some other setting or some other
setting to ACCL while waveform acquisition is stopped on the 701275 (ACCL/VOLT),
the waveforms are no longer drawn. If you set the input coupling to the original
setting, the waveforms are redrawn.
• If you change the contents of the function of the FV setting while the waveform
acquisition is stopped on the 701280 (FREQ), the waveforms are no longer drawn. If
you set the contents of the function to the setting that was present during
measurement, the waveforms are redrawn.
CAUTION
• If the input coupling is AC and the frequency of the input signal is less than 1
Hz, the signal at the input terminal of the module is not attenuated to 1/10 even
if the probe with 10:1 attenuation and input resistance of 10 M
Ω
is used. Make
sure not to apply a voltage that has a signal component less than 1 Hz that
exceeds the maximum input voltage of each module.
• Do not apply a voltage exceeding the maximum input voltage or maximum
allowable common mode voltage of the input modules. This may cause damage
to the input section.
5.5 Selecting the Input Coupling