Rockwell Automation 1404-M4_M5_M6_M8 Powermonitor 3000 User Manual, Firmware rev. 3.0 or LATER - Manual (Page 176)

176 Publication 1404-UM001F-EN-P - November 2009
Chapter 8 Advanced Features
3. Periodically check the event log or capture ready status for an
indication that a sag or swell has occurred.
4. Read the event log to get the timestamp, duration of the
disturbance, the worst case magnitude, and the identifier of the
capture.
5. Find the capture that has the same identifier as the one found in
the event log record by reading the first block from each capture
location.
Read the entire capture from the power monitor. Depending on
the duration of the disturbance, the capture may contain
additional information prior to and during the sag or swell
event.
The sag or swell duration reported in the event log has a tolerance of
± 2x the metering update rate.
Refer to Metering Update Rate on page 60 for more information.
For sag and swell durations less than 500 milliseconds, examining the
oscillograph data can result in a more accurate determination of sag or
swell duration.
References:
IEEE Std 1159-1995, “IEEE Recommended Practice for
Monitoring Electric Power Quality”, page 5,6,12.
The Institute of Electrical & Electronics Engineers Inc,
345 East 47
th
Street,
New York, NY 10017-2394,
ISBN 1-55937-549-3