Rockwell Automation 1441-PEN25-Z Enpac 2500 Data Collector - Manual (Page 79)

Rockwell Automation Publication GMSI10-UM002D-EN-E - August 2012 79
Setting Up Measurements Chapter 2
Magnitude Measurement Definitions
Emonitor and the Enpac 2500 support magnitude measurement definitions.
This topic lists the unique characteristics of the Enpac 2500 that you may need to
know when setting up and collecting magnitude data.
Measurement Units Not Supported in the Enpac 2500 Data Collector
• Magnitude measurement definitions with unit not supported by the
Enpac 2500 map to units of USER (eus) in the data collector. This results
in a process (DC) voltage measurement.
• For a list of supported measurement units, see Measurement Units on
page 68 .
Magnitude Alarms in the Enpac 2500 Data Collector
• The Enpac 2500 supports above, below, in window, and out of window
magnitude alarms.
• You must set Trigger to Yes for any magnitude alarms you want to appear
in the Enpac 2500 during data collection.
• For more on how Emonitor combines alarms before sending them to the
Enpac 2500, see
Alarms and the Data Collector on page 95 .
Collecting Magnitude Measurements in Multiple Frequency Bands
You can set up multiple measurement definitions at a location to collect
magnitude values for individual frequency bands. Use band filters to define the
different frequency bands in the measurement definitions.
Make sure you select None in the Band Filter dialog. This forces the Enpac 2500
to collect a spectrum measurement. After you unload the measurement,
Emonitor calculates the magnitude values in the bands from the spectrum.
If your measurements include both magnitude and phase, the Enpac 2500 can
collect up to eight orders. If your measurements include magnitude only, the
Enpac 2500 can collect up to 200 orders.
Proximity Probe Measurements
• Proximity probes measure the movement of a shaft within a bearing.
• You usually make two types of proximity probe measurements with
magnitude measurement definitions. The dynamic or AC component
indicates the changing (dynamic) distance between the probe and bearing
shaft. The static or DC component indicates the average distance between
the probe and the shaft. This is also referred to as the DC gap.
Dynamic (AC) component
•
Set up a displacement transducer in the Transducer Calibration dialog
with Input type set to AC Coupled and Units set mils or um. Make sure
you enter the Calibration value that converts the voltage to a
displacement.