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47DM OPERATING MANUAL EM-9510-B Rev.6
3. SETTING SCALING VALUES
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INPUT SCALING
Teach Calibration means setting an input value by applying an actual input signal. The calibrated value is called input scal-
ing value.
The input scaling values include Zero and Span.
• Input scaling value Zero is minimum value (0%) of input signal.
• Input scaling value Span is maximum value (100%) of input signal.
e.g. Usage range 2 – 8 kΩ with total resistance 10 kΩ
Input scaling value Zero
Input scaling value Span
2 kΩ
8 kΩ
IMPORTANT
• Set ‘input scaling value Zero + 10% of total resistance ≤ input scaling value Span’.
• 2 kΩ and 8 kΩ are given in the above example. However even when the values are unknown, the input scaling can be
performed by applying 0% and 100% signals of the equipment or device on site by the Teach Calibration.
NOTE
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POTENTIOMETER
• A potentiometer has a wiper, which slides on a fixed resistor. Then the resistance values between 1 and 2, 2 and 3
vary. The variation is used to detect position or angle.
• The 47DM measures the resistance value between 1 and 2 to display.
• Minimum input to be used is input scaling value Zero, and maximum is input scaling value Span.
• When the wiper slides toward 1, the resistance value between 1 and 2 decreases, and when it slides toward 3, it
increases.
Wiper
Total resistance
(nominal resistance)
Input
47DM
Fixed resistor
Potentiometer
Max.
Min.
3
3
2
2
1
1
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DISPLAY SCALING
Display scaling means setting a value to display actually.
The display scaling values include Zero and Span. A decimal point can be set in any position.
• Display scaling value Zero is a display value for the input scaling value Zero.
• Display scaling value Span is a display value for the input scaling value Span.
• Decimal point position can be set in common for both display scaling value Zero and Span.
e.g. Display value 0.000 – 100.000%
Display scaling value Zero
Display scaling value Span
Decimal point position
0.000%
100.000%
0.000 (3 decimal places)
