Programming
Chapter 3
331
Figure 3.27
General AF1 Deviation Function Format After Address Entry
171615141312111076543210
S
Bit No.
Data Address
Digit 2
Digit 3
(LSD)
Input 1
S
Digit 2 Digit 3
Digit 2 Digit 3Digit 1
S
Digit 1
(MSD)
Digit 2 Digit 3
Result Address
Digit 5Digit 4
Result
DE
E = Enable Bit (1 = Function in Progress)
S = Sign Bit (1 = Negative)
D = Done Bit (1 = Function Complete)
MSD = Most Significant Digit
LSD = Least Significant Digit
11586
Digit 6
ER
ER = Error Bit (Set if number of readings = 0)
S
Digit 1
(MSD)
Digit 1
(LSD)
Input 2
Input 3
Number of Inputs
003200
201
202
203
305
306
4. Enter the values of the numbers whose standard deviation is desired in the
input word addresses.
You can enter these numbers from the keyboard of your industrial terminal or
through ladder diagram functions. If we choose to enter values of 200, 201, and
202 into input word addresses 201, 202, and 203 respectively, we obtain the
result shown in Figure 3.28 when the standard deviation function executes. The
result appears in words 305 and 306 as 000.816. The result is truncated but is
accurate to +
0.001.
