Eaton ELC-PB, Programming Manual

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E L C P r o g r a m m i n g M a n u a l
F o r m o r e i n f o r m a t i o n v i s i t : w w w. e a t o n . c o m M N 0 5 0 0 3 0 0 3 E
3 - 4 9 2
API Mnemonic Operands Function
202 SCA L P S
1
, S
2
, S
3
, D Calculation of Proportional Value
Bit Devices Word devices Program Steps
Type
OP
X Y M S K H KnX KnY KnM KnS T C D E F
S
1
* * *
S
2
* * *
S
3
* * *
D *
SCAL,SCLAP: 9 steps
ELC ELCB ELCM
PB PC/PA/PH PV PB PH/PA
32 16 P 32 16 P 32 16 P 32 16 P 32 16 P
Operands:
S
1
: Source value S
2
:
Slope
.
The units of S
2
are 0.001
S
3
:
Offset
D : Destination address
The range for operands
S1, S2, S3
is -32767~32767.
Description:
1. Equation: D = ( S
1
×
S
2
)
÷
1000+ S
3
2. The values for S
2
and S
3
must be calculated using the slope and offset equations below with
decimal rounding to get 16-bit integer values.
3. Slope equation: S
2
= [(Max. destination value – Min. destination value)
÷
(Max. source value –
Min. source value)]
×
1000
4. Offset equation: S
3
=Min. destination value – (Min. source value
×
( S
2
÷
1000))
5. The output curve is as follow:
D
1
Min. destination value
Max. Destination value
Destination value
Source value
Max.
source value
Min.
source value
Program Example 1:
1. S
1
is 500, S
2
is 168 and S
3
is –4. When X0=On, SCAL instruction executes and the scaled
value is stored in D0.
2. Equation
：
D0 = (500
×
168 )
÷
1000+ (-4)=80