Rockwell Automation 441-PEN25 Enpac Ex Data Collector - Manual (Page 59)

Publication GMSI00-UM001A-EN-E - February 2005
Setting Up Measurements 53
The following table shows the transducer specifications in the collection
specifications
.
Note: Make sure you enter the Calibration value that converts the voltage to a known unit such as speed.
Spectrum Measurement Definitions
Emonitor and the Enpac Ex support spectrum measurement definitions. This
topic lists the unique characteristics of the Enpac Ex that you may need to
know when setting up and collecting spectrum data.
• The Enpac Ex cannot collect phase with a spectrum measurement
definition. In other words, do NOT select the Also collect phase data
check box in the Collection Specification dialog box.
• You can choose to have the Enpac Ex collect a spectrum only if a
magnitude measurement at the same location is in alarm. Set the Collect
and store condition in the Edit Storage Specification dialog box to
"On Magnitude Alarm" for the storage specification for the spectrum
measurement definition.
Time synchronous averaging in the Enpac Ex
• Time synchronous averaging cancels out the effects of signals not
related to the synchronizing trigger. Time synchronous mechanical
effects include imbalance, misalignment, eccentricity of bent shafts,
blade passing, and gear meshing.
• Time synchronous averaging requires an external trigger.
• Set up a Collection Specification with the averaging Type set to
"Time Synchronous" and enter the Number of averages. Use a large
number of averages (such as 20 or 30) to get the desired reduction in
non-synchronous effects. For more on supported averaging in the
Enpac Ex, see Number and Type of Averages on page 45.
Table 3.12 Transducer specifications in numeric collection specifications
Name Base Unit Input Type Units Calibration Value DC Offset
Temperature Temperature DC Coupled deg. F See note below. 0
Tachometer Frequency DC Coupled RPM See note below. 0
Manual Entry None Manual Entry None See note below. 0
WARNING
Do not connect the Enpac Ex to an external trigger unless
the area is known to be nonhazardous.