Example

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Prerequisites

Sensor: temperature sensor, measuring range –50 to 100°C

Temperature to be measured 25°C

Order of events with LOGO!Soft Comfort

  1. The sensor converts the temperature from 25°C to a voltage value of 5.0 V.

  2. LOGO! converts the 5.0 V to the standardized value 500.

  3. Using the sensor and measurement range data, LOGO! ascertains the value 0.15 for the gain and the value –50 for the offset.
    According to the formula:

    Analog value = (standardized value x gain) + offset
    LOGO! calculates as analog value:
    Analog value = (500 x 0.15) - 50 = 25

Order of events with LOGO!

  1. The sensor converts the temperature from 25°C to a voltage value of 5.0 V.

  2. LOGO! converts the 5.0 V to the standardized value 500.

  3. From the sensor and measuring range data you must establish the values for gain and offset.
    According to the formula
    s:
    Gain = (maxSensor
    minSensor) / (maxnorm – minnorm)
    and
    Offset = minSensor – (Gain x minnorm)
    it follows that
    Gain = (100 – (-50)) / (1000 – 0) = 0.15
    Offset = -50 – (0.15 x 0) = -50

  4. According to the formula
    Analog value = (standardized value x gain) + offset
    LOGO! calculates as analog value:
    Analog value = (500 x 0.15) - 50 = 25

Additional examples

 

Physical quantity

Electric quantity of sensor

Standardized value

Gain

Offset

Analog value

 

0 V

5 V

10 V

0

500

1000

 

0.01

 

0

0

5

10

 

4 mA

12 mA

20 mA

0

500

1000

 

10

 

0

0

5000

10000

 

0 mA

10 mA

20 mA

0

500

1000

 

1

 

50

50

550

1050

1000 mbar

3700 mbar

5000 mbar

0 V

6.75 V

10 V

0

675

1000

 

4

 

1000

1000

3700

5000

-30 °C

0 °C

70 °C

0 mA

6 mA

20 mA

0

300

1000

 

0.1

 

-30

-30

0

70