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8 - Analog Alarms
Simatic 505 SoftShop
Table 8.1 Analog Alarm V-Flags 1
Bit
Analog Alarm Function
1
1=Enable alarm.
2
1=Disable alarm.
3
1=Process Variable is in high-high alarm.
4
1=Process Variable is in high alarm.
5
1=Process Variable is in low alarm.
6
1=Process Variable is in low low alarm.
7
1=Process Variable is in yellow deviation alarm.
8
1=Process Variable is in orange deviation alarm.
9
1=Process Variable is in rate of change alarm.
10
1=Broken transmitter alarm.
11
1=Analog alarm is overrunning.
12
1=Alarm is enabled.*
13-16
1=Unused.
* If a word is selected for the analog alarm V-Flags, bit 12 is written. If a C or Y is
selected, bit 12 is not used.
NOTE: If you program an analog alarm and do not disable it, the controller begins to
monitor the programmed variable as soon as you place the controller in Run mode.
Sample Rate
Enter a time in seconds in the SAMPLE RATE field.
The sample rate determines how often deviation alarm bits and associated
math are evaluated. Sample rates are programmable in 0.1-second
increments, with alarms checked at least once every two seconds. The
sample rate can be any floating point number between 0.1 and 1.6772 x
10
6
seconds.
Process Variable Address
Enter an address: V, WX, or WY in the PROCESS VARIABLE
ADDRESS field.
A process variable must be specified for each analog alarm. The process
variable can be taken from the following:
•
A word input or output module - The programming table uses a
WX or WY address.
•
A location in V-Memory - The programming table uses an
address in V-Memory.
If you select NONE, the analog alarm does not read an address to obtain
the Process Variable.