Allen-Bradley LOGIX 5000 Reference Manual page 40

Chapter 1 Process Control Instructions
40
If there is no fault present, FaultAlarm is cleared to false if one of the following
conditions is met:
•
Command0Status is true and Device0State is true
•
Command1Status is true and Device1State is true
•
Command2Status is true and Device2State is true
•
FaultTime 0
FaultAlarm cannot be cleared to false when FaultAlarmLatch is true, unless
FaultAlmUnlatch is true and no fault is present.
Mode Alarm Conditions
The mode alarm reminds an operator that a device has been left in Operator
control. The mode alarm only turns on when, in Operator control mode, the
program tries to change the state of the device from the operator's commanded
state. The alarm does not turn on if an operator places a device in Operator
control mode and changes the state. The D3SD instruction checks for mode alarm
conditions, using these rules.
ModeAlarm is When
true Prog2Command
Prog2Command
Prog1Command
Prog1Command
Prog0Command
Prog0Command
false Prog2Command = Command2Status and
Prog1Command = Command1Status and
Prog0Command = Command0Status or
The device is in Override, Hand, or Program control mode
See also
Common Attributes
Structured Text Syntax
Rockwell Automation Publication 1756-RM006K-EN-P - November 2018
Prog2Command and
n-1
Command2Status or
Prog1Command and
n-1
Command1Status or
and
Prog1Command
n-1
Command0Status
on page 537
on page 508