Filter
Top Products
63230-300-212 Chapter 9—Disturbance Monitoring
April 2001 Capabilities of the Circuit Monitor During an Event
117
© 2001 Schneider Electric All Rights Reserved
The circuit monitor 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. Table 9–1 shows the capability of the circuit
monitor to measure electromagnetic phenomena in a power system as
defined in IEEE Recommended Practice for Monitoring Electric Power
Quality (IEEE Standard 1159-95).
When the circuit monitor detects a sag or swell, it can perform the following
actions:
• Performawaveformcapturewith a resolution up to 512 samples per
cycle on all channels of the metered current and voltage inputs. Three
types of automatic event captures are possible: disturbance, adaptive, and
100 ms. See “Types of Waveform Captures” on page 108 in Chapter 8—
Waveform and Event Capture for more about waveform and event
captures. Use
SMS to setup the event capture and retrieve the waveform.
• Record the event in the alarm log. When an event occurs, the circuit
monitor 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 circuit monitor 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
SMS to view the alarm log.
• Forceadatalogentryin up to 14 independent data logs. Use
SMS 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 alarm
LED to show that
a sag or swell event has occurred. From the circuit monitor’sdisplay,alist
of up to 10 of the previous alarms in the high priority log is available. You
can also view the alarms in
SMS.
Table 9–1: Capability of the circuit monitor to measure
electromagnetic phenomena
Categories CM-4000
Short Duration Variations
Instantaneous
Momentary
Temporary
Long Duration Variations
Voltage Imbalance
Waveform Distortion
Voltage Fluctuations
Power Frequency Variations
CAPABILITIES OF THE CIRCUIT
MONITOR DURING AN EVENT