Eaton easyE4 series, Руководство пользователя

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6. Function blocks
6.1 Manufacturer function blocks
6.1.3.4 LS - Value scaling
General
easyE4 base devices provider 32 value scaling function blocks,
LS01 through LS32.
These function blocks can be used to transfer values from one
value range to another. More specifically, a value scaling func-
tion block will take one of the mathematical relationships you
have specified and use it to scale the value at input LS..I1 in
order to then output it, either as smaller value or larger value,
at output LS..QV. The mathematical relationship is based on a
straight line defined by the coordinate pairs X1, Y1 and X2, Y2
(see under “The mathematical relationship is:”).
A typical application is the conversion of values, such as
0…20 mA to 4…20 mA. An easy800 device is provided with
32 value scaling function blocks.
Operating principle
"EN = 1" starts the function block.
"EN = 0" initiates a reset in which the output
QV is reset to 0.
Figure 143: Figure: Scaling the input values - reducing
Source range
Destination range
Figure 144: Figure: Scaling the input values - increasing
The mathematical relationship is follows:
m = Gradient
Y0 = Y offset when X = 0
X1, Y1 = First value pair
easyE4 11/18 MN050009 EN www.eaton.com
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