User`s manual

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MELSEC-Q
8 I/O CONTROL INSTRUCTIONS
(2) Change rate check processing
Performs a change rate alarm check during the change rate alarm check time (CTIM) specified
in the loop tag memory. The change rate alarm check compares the change of the input value
(E1) with the change rate alarm value (DPL) in each execution cycle (
T).
Condition BB3, DPPA
(X
n
X
n-m
)
DPL 1
*2
Others 0
*2: When DPPI or ERRI of the alarm detection inhibition (INH) is 1, DPPA and BB3 turn to 0 since the
alarm is prohibited.
The change rate alarm counter (m) is calculated with the following expression.
CTIM
T
Change rate alarm counter (m)
The change rate alarm counter (m) varies from 1 to m.
However, when the change rate alarm counter (m)
0, no processing is performed.
Example) When the change rate alarm counter (m)
4, processing is perform as shown
below.
Execution cycle
X
n 12
X
n 11
X
n 10
X
n 9
X
n 8
X
n 7
X
n 6
X
n 5
X
n 4
X
n 3
X
n 2
X
n 1
X
n
DPL
X
n m
X
n m
CTIM
Input value (E1)
Change rate alarm (BB3,DPPA)
DPL
DPL
X
n m
(3) Output conversion processing
In the output conversion processing, the following operation is performed and the result of the
operation is stored into BW1 and BW2.
Condition BW1 BW2
E1 000
0 E1 SV1 0
E1 SV1 1
0 E1 SV2 0
E1 SV2 1
ERROR
• When an operation error occurs Error code: 4100