LS Industrial Systems MASTER-K80S, Руководство пользователя

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Chapter 7 Usage of Functions
7- 5 3
5) Scaling function
This function convert automatically range when the inout/output range is not matched
In case that input/output is current , this function is useful that external equapment’ range is not matched each other.
(MK80S series converts range automatically as following : 0 ~ 20mA
√
4 ~ 20mA)
► Conversion method is as below
1) scaling conversion value (A/D conversion) = [(data of 0 ~ 20
㎃
) – 800] x 4000/3200
example) in case of 8
㎃
input at range 0 ~ 20
㎃
before the scaling conversion : 8
㎃
/ 5
㎂
= 1600
after the scaling conversion : (1600 –800) x 1.25 = 1000
2) scaling conversion value (D/A conversion) = [(data of 4 ~ 20
㎃
) x 3200/4000] + 800
example) in case of ‘1000’ output at range 4 ~ 20
㎃
current output value before the scaling conversion : 1000 x 5
㎂
= 5
㎃
current output value after the scaling conversion : (1000 x 0.8) + 800 = 1600
1600 x 5
㎂
= 8
㎃
0
㎃
20
㎃
4000
0
0
㎃
20
㎃
4000
0
4
㎃
800