B+K precision 5490C Series, User Manual

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17
Calculate the corresponding settling time using the RC time constant 0.22 s:
settling time = ln(bias/settled value)*0.22 s
settling time = ln(5 VDC / 2 VDC)*0.22 s
settling time = 0.20 s
The ACV function should be selected after the signal is connected to the digital multimeter's ACV
input or when the signal has been connected, enough extra delay should be given to stabilize the
signal. If the DC bias remains the same, a completely accurate subsequent measurement can be made
without additional stabilization delay.
Step 1: Configure the test leads as shown below.
Step 2: Press the button on the front panel to enter the ACV function interface.
Step 3: Range adjustment.
Press Range and select the range. Auto range (Auto) automatically selects the appropriate range for
measurement based on the input signal. The auto range is adjusted upwards to 110% of the existing
range and down to 10% of the existing range.
Step 4: AC Filter Selection.
The instrument offers three filter options consisting of 3Hz, 20Hz and 200Hz. The filter you choose
should be the highest filter which is less than the frequency of your test signal.