Rockwell Automation 1441-PEN25-Z Enpac 2500 Data Collector - Manual (Page 135)

Rockwell Automation Publication GMSI10-UM002D-EN-E - August 2012 135
Collecting and Reviewing Data Chapter 4
Collect Magnitude and Phase Measurements at Orders
The Enpac 2500 data collector can collect multiple magnitude and phase at
orders of the operating speed. You use a tachometer signal measuring the
operating speed to collect phase data.
Follow these instructions to collect a spectrum for calculating additional
magnitude and phase values at orders of the operating speed.
1. Align the speed reference device, such as a tachometer, in the correct
direction and attach the vibration transducer properly.
2. From the Data Collection screen, press Enter to start ranging the
measurement.
The Enpac 2500 data collector calculates the speed from the tachometer
signal and adjusts the maximum frequency for measuring the spectrum so
that all orders can be calculated from the spectrum:
• If you set Auto Advance to On in the Instrument Configuration screen,
the Enpac 2500 data collector automatically goes to the next point in
the list after it finishes collecting the spectrum.
• If you set Auto Advance to Off then the Signature Measurement screen
appears.
• If you set Fast Averaging to On in the Instrument Configuration screen,
the unit collects the specified number of averages before displaying the
spectrum on the screen.
TIP The message No signal appears if the Enpac 2500 data collector
cannot trigger off the tachometer signal to calculate the speed. If
this happens, fix the speed device signal and connections. The
Enpac 2500 data collector resumes data collection once it can
trigger off the tachometer signal. You must use a key hole or
reflection tape to trigger the tachometer.