User`s guide

Data Storage Configuration
Storage Conventions
186 UMC800 Control Builder User’s Guide Release E
1/01
Disk capacity
The disk capacity (in time) is calculated and displayed once all storage initialization is complete. This
eliminates the need for manual calculations and gives the operator the exact duration of the disk. All file
types in the data storage feature may be configured to stop collecting data when the file is full or to
continue in a circular storage mode (roll-over) where the oldest data is discarded as new data is collected.
When roll-over is not selected, a disk full warning indication is provided in the status line of the display.
The configurer as required may change the percent full limit. A storage buffer in the operator interface
allows changing the disk media without the loss of process data.
Calculation for Data Storage Capacity
Trend Capacity (In Hours) =
Disk factor * (R1)
F1 + (F2 * (R1/R2)
Where:
R1 and R2 are the storage rates (in seconds) for Trend 1 and Trend 2, respectively.
F1 and F2 are the point factors associated with the number of points per trend file.
Disk Factors:
398 Trends files only active
394 Trends files + Alarms and Events
347 Trend files, + alarms and Events + Point Log Files
Number of points in trend
1
14.00
2 3
20.16 26.53
4
33.60
5
38.77
6 7
45.82 50.40
8
56.00
9
63.00
10 11
72.00 84.00
12
84.00
Point Factor (F1 and F2)
File extensions
The following File Extensions are used for the UMC800 Controller’s Data Storage output files:
• LNT for Trend Files
• LNP for Point Log Files
• LNA for Alarm Files
• LNE for Event Files