Mitsubishi Electric R60AD8-G - Scaling Function

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1 FUNCTIONS
1.5 Scaling Function
1.5 Scaling Function
This function performs the scale conversion on digital output values. The values are converted within a specified range
between a scaling upper limit value and scaling lower limit value. This function helps reduce the time taken for creating a scale
conversion program.
The converted values are stored in 'CH1 Digital operation value' (Un\G402).
Concept of scaling setting
Ex.
When the input range is set to -10 to 10V:
For the scaling lower limit value, set a value corresponding to the lower limit value of the input range (-32000).
For the scaling upper limit value, set a value corresponding to the upper limit value of the input range (32000).
Calculating the scaling value
The scale conversion is based on the following formula. (In scale conversion, values are rounded to the nearest whole
number.)
Current: 0 to 20mA, 4 to 20mA, 4 to 20mA (extended mode)
*1
, user range setting (current)
Voltage: 0 to 10V, 0 to 5V, 1 to 5V, 1 to 5V (extended mode)
*1
, user range setting (voltage)
Voltage: -10 to 10V
*1 Although the range of the digital output value in the extended mode is -8000 to 36000, this function performs the scale conversion for
digital output values within the range of 0 to 32000.
When the calculated digital operation value exceeds 32767, the value 32767 is stored as the digital operation
value. When the calculated digital operation value is falls below -32768, the value -32768 is stored.
Setting procedure
1. Set "Scaling enable/disable setting" to "Enable".
[Navigation window]  [Parameter]  [Module Information]  Module model name  [Module Parameter] 
[Application setting]  [Scaling setting]
2. Set values for "Scaling upper limit value" and "Scaling lower limit value".
• Even when the scaling upper limit value and the scaling lower limit value are set so that the change is
greater than the resolution, the resolution will not increase.
• If the relation between the values is the scaling lower limit value > the scaling upper limit value, the scale
conversion can be performed according to a negative slope.
• Set the scaling with the condition "Scaling upper limit value  Scaling lower limit value".
D
X
: Digital output value
D
Y
: Scaling value (Digital operation value)
D
Max
: Maximum digital output value of the input range in use
D
Min
: Minimum digital output value of the input range in use
S
H
: Scaling upper limit value
S
L
: Scaling lower limit value
Item Setting range
Scaling upper limit value -32000 to 32000
Scaling lower limit value
D
X
× (S
H
- S
L
)
D
Max
+ S
L
D
Y
=
D
X
× (S
H
- S
L
)
D
Max
- D
Min
+
D
Y
=
(S
H
+ S
L
)
2