Yokogawa PC-Based MX100 - Manual (Page 34)

1-25
IM MX100-01E
Explanation of Functions
3
2
1
4
5
Index
Scaling Settings When Using a Strain Gauge Type Sensor
The following is an explanation of scaling settings used when measuring physical
quantities such as load and length with a strain gauge type sensor.
The basic relational expression is as follows.
1 mV/V = 2000 µstrain (Equation 1)
Two examples are given below: 1) when rated input and output are listed in the user’s
manual of the strain gauge type sensor, and 2) when listed with the calibration coefficient.
(Hereinafter, “µstrain” will be expressed as “µStr.”)
When Rated Input and Rated Output Are Given
A specific example is given below.
• Rated input 200 N
(set to Y)
• Rated output 0.985 mV/V (set to K)
In this case, these figures indicate that if a 200 N load is applied, 0.985 mV/V is output.
From the relationship in equation 1, if 200 N is applied,
an output of 0.985 mV/V=0.985 × 2000=1970 µStr is attained.
In other words, for each 1 N, 1970 µStr/200 N= 9.85 µStr/N is output.
Therefore, the scaling settings are entered as follows.
When Measuring at 50-150 N
Scale minimum: 50 (set to Smin)
Scale maximum: 150 (units: N) (set to Smax)
therefore,
Span minimum: 50 × 9.85 µStr/N = 492.5 µStr
Span maximum: 150 × 9.85 =1477.5 µStr
can be set.
Thus, the measuring range is 2000 µStr.
Generally, the range is as follows.
Using the symbols that have appeared in the explanation thus far, after setting the scale
maximum and minimum, the values are as follows.
Span minimum = [(K(mV/V) × 2000) / Y(unit)] × Smin ([µ]Str)
Span maximum = [(K(mV/V) × 2000) / Y(unit)] × Smax ([µ]Str)
1.7 Functions of the 4-CH, Medium-Speed Strain Input Module (-B12, -B35, and -NDI)