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9410 series
Related Topics
•
Alarms overview
Waveform recording overview
Your meter is able to record voltage and current waveform information.
Waveform information is used to help identify power system disturbances, which are
an increasing concern for industrial plants, hospitals, data centers and other facilities
where the equipment is sensitive to voltage or current sags, swells, and momentary
interruptions. Waveform information is also used to help ensure compliance with power
quality standards.
In addition to measuring and recording numerical values for voltage and current, your
meter can also capture the sinusoidal waveform data. The current and voltage
waveform data provides additional information for analysis of the system’s power
quality or a power quality event.
You can manually trigger waveform recordings or configure them to trigger
automatically when there is a power quality or power system event. For waveform
recording to trigger automatically, you must enter your system’s nominal (normal)
voltage and current values, and then the amount of deviation from the nominal
required to trigger waveform recording.
Your meter’s waveform data storage format is defined by:
•
Cycles: the number of cycles (based on your power system’s frequency) included in
the waveform (its duration).
•
Samples: samples per cycle, which is the number of waveform data points
collected in each cycle.
This gives you the option to record a lot of information for a very short duration or less
information over a longer duration. You can also configure a delay in starting waveform
recording which allows you to record pre- and post-event data.
You can use your meter to detect ITI (CBEMA) - type disturbances, and can determine
information regarding the magnitude and duration of each disturbance. This
information can be used by your energy management system to plot the disturbance
on a CBEMA curve.
COMTRADE waveform data is available from your meter.
NOTE:
If you are generating COMTRADE waveform information, the associated
waveform recorders cannot be modified unless COMTRADE is disabled. If the
waveform recorders are not configured identically, COMTRADE waveform information
will not be generated.
Key terms
Term
Definition
COMTRADE
COMmon format for TRAnsient Data Exchange (COMTRADE) is a common format
for waveform data.
ITI (CBEMA)
A curve that graphically describes an AC input voltage envelope which can be
typically tolerated by information technology equipment. Meter waveform
information is plotted on this curve to help evaluate power quality.
Nominal
The normal or usual parameter value. For example, the nominal voltage for many
power systems is 120 V.
Sag
A power event where the voltage or current drops below the nominal value.
Swell
A power event where the voltage or current rises above the nominal value.
See the ION Reference, available from www.usa.siemens.com/pds, for more
information on the Waveform Recorder module and its settings.
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