Mitsubishi Electric a2 Series Programming Manual page 169

α
2 Simple Application Controllers
FB Name
Time Switch
m
[TSm]
Counter
[CN]
U/D Counter
[UD]
Compare
[CP]
Analog
Output
Offset
Gain
[OG]
Display
[DP]
Zone
Compare
[ZC]
Schmitt
Trigger
[ST]
FB Symbol Description of Function Block
The Time Switch maintenance Function
0 0 0
Block uses a predefined time schedule to
P
control the ON and OFF status of the
output. The function block can be setup
T m S
from the TopMenu via the front panel keys.
The Counter Function Block increments the
0 0 0
current value by one as and when the input
I P O
pin receives a signal. When the current
C value reaches the set value the output is set
C N
ON. The counter current value is reset as
and when the clear pin receives an input.
The Up/Down Function block positively or
U 0 0 0
negatively increments the counter until a
D P O set value is reached thereby setting the
output ON. A preset signal can also equal
C
U D the set value regardless of the current value
P
for the function block and thereby setting
the output ON.
The Compare Function Block monitors the
0 0 0
current value of the input pin in relation to a
I P O
preset expression. The expression consists
of =,>,>=,<,<= or <>. If the compared value
C P
satisfies the expression subsequently the
output pin is set on.
0 0 0
The Analog Output function takes a digital
value input and delivers a corresponding
I
P
analog voltage or current to a selected
channel on the AL2-2DA module.
A O
0 0 0
The Offset Gain Function Block is based
I P
upon a linear function Y=A/B∗X+C to which
the value obtained from an analog input
O G
(X:A01-A08) is set.
0 0 0
The Display Function Block is used as an
interface between the user and the devices
I P
held within the controller. Current values,
timer messages, user-defined messages
D P
can be read.
T h e Z o n e C o m p a r e F u n c t i o n B l o c k
0 0 0
identifies whether the input value lies within
I P O
a specified upper and lower limited zonal
area and if so changes the status of the
Z C
output accordingly.
T h e S c h m i t t Tr i g g e r F u n c t i o n B l o ck
0 0 0
compares an input value to preset high and
I P O low limits. The output is ON when the input
value reaches the high limit and then falls
S T
below the lower limit. The function only
processes the data when the function block
is receiving an input signal.
Appendix 8
Memory
Section
Use
*2 6.10
16 Byte 6.11
22 Byte 6.12
17 Byte 6.13
17 Byte 6.14
22Byte 6.15
*4 6.16
20 Byte 6.17
19 Byte 6.18
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