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Watlow PPC-2000 User Manual

Page 220

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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