Rockwell Automation 1440-VAD02-01RA XM-123 Aeroderivative Module - Manual (Page 81)

Publication GMSI10-UM003D-EN-P - May 2010
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Latch Enable Determines whether the startup/coast-down trend is
latched or unlatched.
Latched means that subsequent startup/coast-down
trends are ignored after the initial
startup/coast-down. This prevents the trend data
from being overwritten with new data until the
trigger is manually reset (click Reset Trigger button).
Unlatched means that the startup/coast-down trend
data is overwritten with new data every time the
machine speed crosses into the speed range.
Check means latched
Clear means unlatched
Record Interval The change in speed between consecutive records.
Note: If you enter a Record Interval, the Maximum
Trend Span is automatically updated.
1 to 3600 RPM
Maximum Trend Span The maximum change in speed that can be covered
by the trend data (Number of Records x Record
Interval).
Note: If you edit the Trend Span, the Record
Interval is automatically updated.
RPM
Minimum Speed The lesser limit of the speed range in which records
are collected in the startup/coast-down trend. This
value must be less than the Maximum Speed
value. RPM
Startup/Coast-down Trend
Considerations:
•
The XM module collects a startup
trend when the machine speed rises
through the Minimum Speed +
8 RPM, and stops when the machine
speed crosses either the Minimum
Speed or the Maximum Speed.
The module collects data only when
the machine speed is increasing. It
does not collect data if the machine
speed is constant or decreasing.
•
The XM module collects a
coast-down trend when the machine
speed falls through the Maximum
Speed - 8 RPM, and stops when the
machine speed crosses either the
Minimum Speed or the Maximum
Speed. The module collects data
when the machine speed is
decreasing or increasing during a
coast-down trend (for example, a
coast-down restart).
Maximum Speed The greater limit of the speed range in which records
are collected in the startup/coast-down trend. This
value must be greater than the Minimum Speed
value.
SU/CD Trend Parameters
Parameter Name Description Values/Comments