Rockwell Automation 1426 PowerMonitor 5000 Unit - Manual (Page 95)

Rockwell Automation Publication 1426-UM001F-EN-P - November 2013 95
Power Quality Monitoring Chapter 5
Waveform Capture Application Considerations
The PowerMonitor 5000 captures one waveform record at a time. It is possible
that more than one triggering event can occur in a short time. The starting point
of a waveform capture is determined by the first triggering event and the defined
pre-event cycles. If fewer cycles of data are available, then the first available cycle
is the starting point.
If more than one triggering event occurs during a waveform capture, the capture
duration extends to include the duration of the event that ends latest, plus the
post-trigger cycles. A waveform record that includes more than one triggering
event is referenced in all power quality log records of the triggering events.
Pre-event or post-event cycle settings that are changed during a waveform capture
do not take effect until the next capture. Any change to
Configuration.Metering_Basic immediately ends a waveform capture that is in
process.
In the unlikely event that the PowerMonitor 5000's resources are overstressed so
that it is unable to write a waveform record to non-volatile memory in a timely
fashion, the in-process waveform record ends with the latest cycle captured in
RAM.
Commands
The following waveform-related commands are found in the
Command.System_Registers table.
Command Word 2
Set this command word value to execute the listed action. These are the
selections:
• 14 = Trigger Waveform
• 15 = Clear Waveform
Clear Waveform operates by using the value contained in the tag listed below.
The default value is zero.
Clear Waveform File ID
Waveform File ID, the choices are the following:
• 0 = Clear All
• 1…32767 = Clear selected; if the ID does not exist, the command is
ignored