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Product Directory > Condition Monitoring > Protection Systems > XM-120 & 121 Dynamic Measurement Modules

XM-120 & 121 Dynamic Measurement Modules

Introduction Communications Inputs Tachometer Outputs Indicators Signal Conditioning
Complex Data Measured Parameters Data Buffers Alarms Relays Max Speed Capture Non-Volatile Configuration
Power Approvals Environmental Physical Ordering Informaton

Data Buffers


Trend Buffer:

Stores a set of records containing measured parameters in response to a trigger event.

  • Trend Record: 1 to 16 parameters
  • Trend Interval: 1 to 3600 seconds
  • Trigger: The trend is saved when a specified relay actuates, or on command from an XM-440, host or controller.
  • Capacity: 170 to 2048 records depending on the number of parameters stored.


Trip Spectra or Time Waveform:

The current time waveforms or spectra are saved upon the same trigger event defined for the Trend Buffer (above).


Speed Buffer:

Stores a startup/coast-down trend of measurement parameters in response to changes in speed.

  • Su/Cd Record: 1 to 16 parameters
  • Su/Cd Interval: 1 to 3600 RPM
  • Trigger: Records are sampled while speed is between user specified minimum and maximum values.
  • Sampled while speed is increasing only during startup.
  • Capacity: 113 to 512 records depending on the number of parameters stored.
  • Su/Cd buffer may be latched to preserve the initial trip data in the event of subsequent trips.