Schneider Electric PM850 Manual De Usuario

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© 2011 Schneider Electric. All Rights Reserved.
63230-500-225A2
PowerLogic
TM
 Series 800 Power Meter
3/2011
Chapter 9—Disturbance Monitoring (PM870)
67
— Use waveform capture to determine exact disturbance characteristics to compare 
with equipment sensitivity
— Justify purchase of power conditioning equipment
— Distinguish between equipment malfunctions and power system related problems
Develop disturbance prevention methods
— Develop solutions to voltage sensitivity-based problems using actual data
Work with the utility
— Discuss protection practices with the serving utility and negotiate suitable changes 
to shorten the duration of potential sags (reduce interruption time delays on 
protective devices)
— Work with the utility to provide alternate “stiffer” services (alternate design practices)
Capabilities of the PM870 During an Event
The PM870 calculates rms magnitudes, based on 128 data points per cycle, every 1/2 
cycle. This ensures that even sub-cycle duration rms variations are not missed. 
The power meter is configured with 12 default voltage disturbance alarms for all voltage 
channels. Current sag and swell alarms are available by configuring custom alarms. A 
maximum of 12 disturbance alarms are available. When the PM870 detects a sag or swell, 
it can perform the following actions:
Perform a waveform capture with a resolution from 185 cycles at 16 samples per 
cycle on one channel down to 3 cycles at 128 samples per cycle on all six channels of 
the metered current and voltage inputs (see Figure 8–1 on page 63). Use PowerLogic 
software to set up the event capture and retrieve the waveform.
Record the event in the alarm log. When an event occurs, the PM870 updates the 
alarm log with an event date and time stamp with 1 millisecond resolution for a sag or 
swell pickup, and an rms magnitude corresponding to the most extreme value of the 
sag or swell during the event pickup delay. Also, the PM870 can record the sag or swell 
dropout in the alarm log at the end of the disturbance. Information stored includes: a 
dropout time stamp with 1 millisecond resolution and a second rms magnitude 
corresponding to the most extreme value of the sag or swell. Use PowerLogic software 
to view the alarm log. 
NOTE: The Power Meter display has a 1 second resolution.
Force a data log entry in up to 3 independent data logs. Use PowerLogic software to 
set up and view the data logs.
Operate any output relays when the event is detected. 
Indicate the alarm on the display by flashing the maintenance icon to show that a sag 
or swell event has occurred.