Scaling Function - Mitsubishi Electric MELSEC-Q Series User Manual
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3 SPECIFICATIONS
3.2.14 Scaling function
3 - 39
The scaling function scales the measured value and stores it in Scaling value (buffer
memory address: 196, 212).
The conversion method differs for thermocouple input and for micro voltage, voltage,
and current input.
The conversion method is automatically selected depending on the setting of Input
range (buffer memory address: 32, 64).
(1) Thermocouple input
The measured value within the scaling range set by Scaling range upper limit
value (buffer memory address: 197, 213) and Scaling range lower limit value
(buffer memory address: 198, 214) is scaled to the scaring width set by Scaling
width upper limit value (buffer memory address: 199, 215) and Scaling width
lower limit value (buffer memory address: 200, 216).
The following describes the calculation method of scaling value.
S
= ( S
- S
CV
CWU
S
: Scaling value
CV
S
: Scaling width upper limit value
CWU
S
: Scaling width lower limit value
CWL
T
: Measured temperature value
EPV
S
: Scaling range upper limit value
CRU
S
: Scaling range lower limit value
CRL
Example) When scaling the temperature to a percentage (%)
When scaling the temperature 360
3600) with the following setting.
Scaling range: -100 to 500
value = 5000)
Scaling width: 0 to 100% (lower limit value = 0, upper limit value =
100)
Scaling value = (100 - 0)
= 76.6666
= 77 (%)
Rounded to the whole number.
POINT
The scaling is performed by the above method even if the upper limit value is set
smaller than the lower limit value for the scaling range upper/lower limit value and
scaling width upper/lower limit value.
When the upper limit value is set equal to the lower limit value, the scaling is not
performed.
When the measured value out of the scaling range is measured, the values set with
the scaling width upper/lower limit value are stored.
T
- S
EPV
CRL
)
CWL
S
- S
CRU
CRL
(lower limit value = -1000, upper limit
3600 - (-1000)
5000 - (-1000)
+ S
CWL
(temperature conversion value:
+ 0
MELSEC-Q
3 - 39
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