Chapter 4 Features and Functions

Alarm Limits

Using Alarms With the Multifunction Module

You can configure the instrument to generate an alarm when a specific bit pattern or bit pattern change is detected on a digital input channel or when a specific count is reached on a totalizer channel. These channels do not have to be part of the scan list to generate an alarm. Alarms are evaluated continuously as soon as you enable them.

∙The digital input channels are numbered “s01” (lower byte) and “s02” (upper byte), where s represents the slot number. The totalizer channel is numbered “s03”.

∙Alarms are evaluated continuously on the multifunction module, but alarm data is stored in reading memory only during a scan.

∙Each time you start a new scan, the instrument clears all readings (including alarm data) stored in reading memory from the previous scan. However, alarm data stored in the alarm queue from the multifunction module is not cleared. Therefore, although the contents of reading memory are always from the most recent scan, the alarm queue may contain data that occurred during previous scans or while the instrument was not scanning.

∙Front-Panel Operation: To configure an alarm on a digital input channel, choose from the following items and then set the desired bit pattern. Set each bit to “0”, “1”, or “X” (don’t care). You can either specify that an alarm will occur when certain bits change or when a specific 8-bit pattern is read.

NOT PATTERN , PATTERN MATCH

￿￿￿￿ ￿ ; ￿ ￿ ￿ ￿ ￿ ￿ ￿ % , 1 ￿

Bit 7

Bit 0

To configure an alarm on a totalizer channel, select a high limit and then set the desired count for the selected alarm.

HI ALARM ONLY

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