Rockwell Automation DAG6.5.8 APPLICATION GUIDE SCADA SYSTEM - Manual (Page 129)

Publication AG-UM008C-EN-P - February 2005
Configuring MicroLogix 1100/1200/1500 Controllers 3-61
String Length of Record
The size of a record is limited so that the length of the maximum
formatted string does not exceed 80 characters. The following table
can be used to determine the formatted string length.
For queue 5, the formatted string length is 29 characters, as shown
below:
= 8 + 1 + 6 + 1 + 6 + 1 + 6 = 29 characters
Number of Records
Using Queue 5 as an example, each record consumes:
Each record consumes 10 bytes. So if only one queue was configured,
the maximum number of records that could be stored would be 4915.
The maximum number of records is calculated by:
Maximum Number of Records = Data Log File Size/Record Size
= 48K bytes/10 bytes
= (48)(1024)/10
= 4915 records
Data Memory Consumed Formatted String Size
delimiter 0 bytes 1 character
word 2 bytes 6 characters
long word 4 bytes 11 characters
date 2 bytes 10 characters
time 2 bytes 8 characters
Data Time N7:11 I1:3.0 I1:2.1
Characters 8 1 6 1 6 1 6
Record Field Memory Consumption
Time 2 bytes
N7:11 2 bytes
I1:3.0 2 bytes
I1:2.1 2 bytes
Integrity Check 2 bytes
Total 10 bytes