Instruction Manual

Chapter 5: LogicPro and Modbus Reference PPC-2000 User’s Guide
192 Watlow Anafaze Doc.# 30002-00 Rev 2.3
Table 5.30 Alarm and Control Functionality
Alarm Acknowledge Flags
Each Alarm Acknowledge register contains a 16-bit word. When
an alarm occurs and it is not a control alarm, the corresponding
Alarm Acknowledge bit is set equal to 1. The bit remains set even
if the corresponding alarm condition is corrected. Read the
Alarm Acknowledge bits to determine if there are
unacknowledged alarms. Set bits to 0 to acknowledge the
corresponding alarm.
Table 5.31 Alarm Acknowledge
Alarm Enable Flags
Alarm Status and Alarm Acknowledge bits are set when the process
variable crosses the process or deviation limit only when the
corresponding alarm enable bit set to 1. Set the alarm enable
bit to 1 for each alarm limit to be monitored. Set the alarm
enable bit to 0 to ignore the corresponding alarm.
Table 5.32 Alarm Enable/Disable
NOTE! The range and precision of the process limits and
deviation offsets are the same as that of the
corresponding input. See Table 5.10 on page 170.
Value Function Description
0 Alarm
Standard alarm function. Digital output, if
set, activates on alarm, deactivates when
channel is not in alarm. Global alarm
output activates and requires alarm
acknowledgment to clear.
1 Control
Digital output, if set, activates on alarm,
deactivates when channel is not in alarm.
Global alarm output does not activate. No
alarm acknowledgment required to clear.
Value Description
0 Acknowledged alarm
1 Unacknowledged alarm
Value Description
0 Disable
1 Enable