NF ZM2371, Инструкция по эксплуатации

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3.5 Basic Operations
3-47 ZM2371/ZM2372

Direct correction frequencies
Whether the zero correction is made over full frequency range or at specific frequency only
(spot correction) can be selected. DC is measured at all times.
When the correction is made over full frequency range, the frequency points at which
correction value is measured directly are as follows:
DC / 0.001 / 0.002 / 0.005 / 0.01 / 0.015 / 0.022 / 0.033 / 0.05 / 0.07 / 0.1 / 0.15 / 0.22 /
0.33 / 0.5 / 0.7 / 1 / 1.5 / 2.2 / 3.3 / 5 / 7 / 10 / 15 / 20 / 30 / 40 / 55 / 70 / 90 / 110 / 130 /
165 / 220 / 330 / 400 / 500 / 600 / 800 /1k / 1.2k / 1.5k / 2k / 2.5k / 3k / 4k / 5k / 6k / 8k
/ 10k / 12k / 15k / 20k / 25k / 30k / 40k / 50k / 60k / 80k / 100k [Hz]
For other frequencies, the correction value is obtained by interpolation. At a point near
resonance point where the correction value varies largely depending on the frequency, an
error by interpolation becomes large, and therefore it is recommended to use the spot
correction.

Setting of correction lower limit frequency (common to OPEN correction and SHORT
correction)
It will take time for measurement as the frequency becomes low. Accordingly, set the lower
limit frequency appropriately when the correction is made in full frequency range. The
initial value is 40Hz.
First, press the
_ SHIFT _ + [OPEN]
keys to display the OPEN correction menu, and select
Low FREQ with the
_ 4 _
key to display the correction lower limit frequency setting menu
shown below.
L o w e r F r e q u e n c y = 1 0 0 H z
Current setting
1mHz to 1kHz
Range of settable values
Set the lowest frequency among frequencies to be measured. The correction lower limit
frequency can be set with two significant digits (frequency
≧
10mHz) or 1mHz (frequency
< 10mHz).
If a setting is made or the EXIT operation is performed, one-previous menu comes back.
The correction lower limit frequency is displayed in the OPEN correction menu.
Correction lower limit frequency
O P E N C o r r e c t i o n : O F F 1 0 0 H z - F R M T: C p - G
First line
The correction value is measured in a range from the highest direct correction frequency
point which does not exceed the set correction lower limit frequency to the measurement
upper limit frequency. For the correction value at a direct correction point where a new
correction value is not measured, the last value is held and used for correction calculation as
it is. When the correction lower limit frequency is lowered, the interpolated correction value
may be incorrect unless the correction value is measured again.
The correction lower limit frequency is common to the OPEN correction and SHORT
correction. If Low FREQ is selected with the SHORT correction menu, same correction lower
limit frequency setting menu as that of OPEN correction is displayed. Also, the correction
lower limit frequency is displayed in the SHORT correction menu, too.