Yokogawa Value Series FX1000 - Manual (Page 101)

3-28 IM 04L21B01-01EN
3.13 Using the Log Scale to Perform Measurements
(/LG1 Option)
Log Scale Display Function
You can apply a logarithmic voltage that has been converted from a physical value to the
FX, and then use the FX’s log scale (logarithmic scale) to display and record the physical
value. The FX supports four types of input signals.
• Logarithmic Input
This is referred to as “ log input.” Log input is input in which the voltage corresponds
to logarithmic values of physical values.
• Input That Is Linear on a Logarithmic Scale
Log linear input is input in which the voltage values correspond to the logarithmic
values of physical values at each decade division (for example, 1 × 10 2 ) and in which,
within each decade, the voltage values correspond linearly to physical values.
• Pseudo Log Input
This input supports pseudo logs.
• Nonlinear Log Input
This input supports nonlinear logs on which calibration correction (/CC1 option) is
applied. Calibration correction is performed using voltage values.
On the trend display, the FX displays waveforms with the log scale. Digital values are
displayed as exponents (for example, 1.2E+03).
Log scale
Digital values
Restrictions
Partial
You cannot set the partial display on a channel that is set to log scale.
Differential Computation between Channels
If you set the reference channel of a differential computation between channels to a
channel that is set to log scale, an error will be returned as the measured result of the
differential computation between channels.
Calibration Correction (/CC1 option)
You cannot set calibration correction on a channel whose log scale mode is set to
LogType2.
Computation Channels (/M1, /PM1, and /PWR1 options)
Do not include channels that are set to log scale in a computation channel expression. If
you include these channels, an error will be returned as the measured result.
Report Function (/M1, /PM1, and /PWR1 options)
You cannot create reports for channels that are set to log scale. An error will be returned
as the result of report computations on channels that are set to log scale.