Rockwell Automation 1441-DYN25-Z Dynamix 2500 Data Collector User Manual
Page 90
90
Rockwell Automation Publication 1441-UM001B-EN-P - September 2012
Chapter 3
Setting Up Measurements
To Set Up Multiple Measurement Definitions for Magnitude and Phase
You create only one measurement definition for magnitude and phase at each
order. The Also collect phase data checkbox in the Collection Specification
dialog box determines whether you also want to collect phase as well as
magnitude data.
follow these instructions to set up multiple measurement definitions for
magnitude and phase.
1.
Create a new measurement definition by selecting Magnitude in the Data
Type column in the Measurement Definition pane.
2.
Select the units for the measurement definition, using a dynamic unit such
as g’s, m/s2, ips, mm/s, mils, um, or V.
3.
Select the measurement filter.
4.
Collect the magnitude and phase at an order, select a band filter centered
on the order.
For example, select (create if necessary) a first order band filter with a Low
cutoff of 0.8 Orders, and a High cutoff of 1.2 Orders.
Measurement Filters on page 67
for details and the examples on the
following pages.
5.
Select the collection specification.
Collecting magnitudes
The Dynamix 2500 data collector can collect magnitude only at the first
through the eighth orders. If you request additional orders, the Emonitor
software calculates magnitude values at additional orders from the
spectrum after unloading the data.
Collecting more orders
than requested
The Dynamix 2500 data collector may collect more orders than
requested, but it does not collect fewer than requested. Only the
requested values are unloaded into the Emonitor software.
Displaying phase value
The Dynamix 2500 data collector may display a phase value that differs
from the value that appears in the Emonitor software by up to one
degree.
Require trigger signal
Phase and magnitude measurements at orders require a trigger signal.
This can be from the internal laser tachometer or from an external
trigger source such as a key phasor.
IMPORTANT
It is very important that order band filters be centered on the
order. For example, 0.7…1.3 orders, 0.8…1.2 orders, 0.9…1.1
orders, and so forth. If you do not center the band filters,
magnitude and phase readings may not be accurate.
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Description