703
FX
3G
/FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
29 Data Table Operation – FNC250 to FNC269
29.2 FNC257 – BAND / Dead Band Control
21
FN
C
160-
FN
C
169
R
eal T
im
e C
lo
ck
22
FN
C
170-
FN
C
179
Exter
nal D
ev
ice
23
FN
C
180
Al
ter
nate
In
str
uc
tions
24
FN
C
181-
FN
C
189
O
ther
s
25
FN
C
190-
FN
C
199
B
lock D
ata
26
FN
C
200-
FN
C
209
C
har
acter
S
tring
27
FN
C
210-
FN
C
219
Da
ta
28
FN
C
220-
FN
C
249
Da
ta
29
FN
C
25
0-
FN
C
26
9
D
ata T
abl
e
30
FN
C
270-
FN
C
274
Ex
-D
ev
ice
29.2
FNC257 – BAND / Dead Band Control
Outline
This instruction provides the upper limit value and lower limit value of the dead band for an input numeric
value, and controls the output value using these limit values.
1. Instruction format
2. Set data
3. Applicable devices
Explanation of function and operation
1. 16-bit operation (BAND and BANDP)
Depending on how the input value (16-bit binary value) specified by
compares to the dead band range
between
and
, the output value
is controlled.
Operand Type
Description
Data Type
Lower limit value of the dead band (no-output band)
16- or 32-bit binary
Upper limit value of the dead band (no-output band)
Input value controlled by the dead band
Device number storing the output value controlled by the dead band
Oper-
and
Type
Bit Devices
Word Devices
Others
System User
Digit Specification
System User
Special
Unit
Index
Con-
stant
Real
Number
Charac-
ter String
Pointer
X Y M T C S D
.b KnX KnY KnM KnS T C D R U
\G
V Z Modify K H
E
"
"
P
3
3
3
3
3 3 3 3
3
3
3 3
3
3
3
3
3 3 3 3
3
3
3 3
3
3
3
3
3 3 3 3
3
3
3
3
3
3 3 3 3
3
3
P
FNC 257
BAND
D
Mnemonic
Operation Condition
16-bit Instruction
9 steps
BAND
BANDP
Mnemonic
Operation Condition
Continuous
Operation
Pulse (Single)
Operation
32-bit Instruction
17 steps
DBAND
DBANDP
Continuous
Operation
Pulse (Single)
Operation
S
1
S
2
S
3
D
S
1
S
2
S
3
D
S
3
S
1
S
2
D
FNC257
BAND
Output
( )
Lower limit value of
dead band
S
1
S
2
D
S
3
Input
value
Output value
Command
input
In the case of “ Lower limit value > Input value” .... Input value
−
Lower limit value
→
Output value
In the case of “ Upper limit value < Input value” .... Input value
−
Upper limit value
→
Output value
In the case of “ Lower limit value
≤
Input value
≤
Upper limit value” .................................0
→
Output value
S
1
S
2
S
1
S
3
S
3
S
3
S
2
S
3
S
3
S
1
S
2
D
D
D
Output value( )
Output
D
Input value ( )
S
3
S
1
Upper limit value of
dead band
( )
S
2
Output value = 0