Siemens SPS starter kit 6ED1057-3BA00-0AA8 12 Vdc, 24 Vdc 6ED1057-3BA00-0AA8 Ficha De Dados
Códigos do produto
6ED1057-3BA00-0AA8
LOGO! functions
4.3 Special functions
LOGO!
130
Manual, 06/2014, A5E33039675
4.3.6
Calculating the gain and offset of analog values
A sensor is connected to the analog input and converts a process variable into an electrical
signal. This value of signal lies within the typical range of this sensor.
LOGO! always converts the electrical signals at the analog input into digital values from 0 to
LOGO! always converts the electrical signals at the analog input into digital values from 0 to
1000.
LOGO! internally transforms a voltage of 0 V to 10 V at input AI to a range of values from 0
LOGO! internally transforms a voltage of 0 V to 10 V at input AI to a range of values from 0
to 1000. LOGO! interprets an input voltage exceeding 10 V as internal value 1000.
Because you cannot always process the range of values from 0 to 1000 as predetermined by
Because you cannot always process the range of values from 0 to 1000 as predetermined by
LOGO!, you can multiply the digital values by a gain factor and then shift the zero of the
range of values (offset). This allows you to output an analog value to the LOGO! onboard
display that is proportional to the actual process variable.
Parameter
Minimum
Maximum
Input voltage (in V)
0
≥ 10
Internal value
0
1000
Gain
-10.00
+10.00
Offset
-10000
+10000
Mathematical rule
Actual value
Ax =
(internal value at input Ax • gain) + offset
Gain and offset calculation
LOGO! calculates the gain and offset based on the relevant high and low values of the
function.
Example 1:
The available thermocouples have the following technical data: -30 °C to +70 °C, 0 to 10
Example 1:
The available thermocouples have the following technical data: -30 °C to +70 °C, 0 to 10
VDC (that is, 0 to 1000 in LOGO!).
Actual value
= (internal value • gain) + offset, thus
-30 = (0 • A) + B, that is, offset B = -30
+70 = (1000 • A) -30, that is, gain A = 0.1
Example 2:
A pressure sensor converts a pressure of 1000 mbar into a voltage of 0 V, and a pressure of
+70 = (1000 • A) -30, that is, gain A = 0.1
Example 2:
A pressure sensor converts a pressure of 1000 mbar into a voltage of 0 V, and a pressure of
5000 mbar into a voltage of 10 V.
Actual value
= (internal value • gain) + offset, thus
1000 = (0 • A) + B, that is, offset B = 1000
5000 = (1000 • A) +1000, that is, gain A = 4
5000 = (1000 • A) +1000, that is, gain A = 4