User`s manual

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MELSEC-Q
3 DATA USED FOR PROCESS CONTROL INSTRUCTIONS AND HOW TO
SPECIFY DATA
S: Stored by the system
Table 3.1 ALM details list
U: Set by the user
Name Abbreviation Description
Flag
establishment
conditions
Stop alarm SPA
Shows the loop stop status. Changes the loop mode to manual.
Conducts stop alarm processing for the output value (BW) and alarm
signal.
U
Output change rate limit alarm DMLA
Conducts the change rate limiter for the input data and outputs the
change rate alarm. (For the output change upper limit value/control
value).
S
Output open alarm OOPA
Shows that it has changed to open status when the operation output
signal has become disconnected, etc.
S
Sensor alarm SEA Sensor error alarm S
Upper upper limit alarm HHA
Checks the upper limit value of the process equipment upper limit, and
outputs an alarm if the process value is higher than the upper limit
value.
S
Lower lower limit alarm LLA
Checks the lower limit value of the process equipment lower limit, and
outputs an alarm if the process value is lower than the lower limit value.
S
Upper limit alarm PHA
Checks the upper limit value of the process value, and outputs an alarm
if the process value is higher than the upper limit value.
S
Lower limit alarm PLA
Checks the lower limit value of the process value, and outputs an alarm
if the process value is lower than the lower limit value.
S
Positive direction change rate
alarm
DPPA
Outputs an alarm if the change rate is higher than the upward trend
change rate range.
S
Negative direction change rate
alarm
DPNA
Outputs an alarm if the change rate is lower than the downward trend
change rate range.
S
Deviation large alarm DVLA
Conducts an error check and then outputs an alarm if over. In addition,
if the error check determines that the deviation is completely less than
the warning value and the error is reduced by a set value from the
warning value then the deviation large alarm will be released.
S
Output upper limit alarm MHA
Conducts a check using the upper/lower limiter and if the limiter results
are larger than the input upper limit value an alarm is output.
S
Output lower limit alarm MLA
A check is conducted by an upper/lower limiter and if the limiter results
are smaller than the input lower limit value an alarm is output.
S
(b) INH
This prohibits alarm detection for each item. In addition, the alarms prohibited by INH are
not detected. (The INH bits 0 to 11 correspond to the bits 0 to 11 of ALM.)
Trucking flag
(We ask the user not touch this.)
b15 b12 b8 b4 b0b1b2b3b5b6b7b9b10b11b13b14
E
R
R
I
T
R
K
F
D
M
L
I
S
E
I
L
L
I
P
L
I
D
P
N
I
M
H
I
O
O
P
I
H
H
I
P
H
I
D
P
P
I
D
V
L
I
M
L
I
All alarm detection prohibited