Rockwell Automation 1441-PEN25-Z Enpac 2500 Data Collector - Manual (Page 174)

174 Rockwell Automation Publication GMSI10-UM002D-EN-E - August 2012
Chapter 6 Multi-channel Measurements
Multi-channel Cursor, Display Expand, and Full Scale Adjustments
For multi channel measurements, the cursor operates simultaneously on all traces
(even if one is hidden). This is also true for Full Scale adjustments using the Up
and Down arrows (amplitude axis). You can use the + and - keys to adjust the
display and expand (frequency/time axis).
Independent Autoranging
For two channel measurements, autoranging is performed simultaneously on
both channels. This lets you use two probes of differing sensitivity. You can
analyze two axes of differing amplitudes while ensuring optimum gain setting for
each channel.
In all cases, the same filters, integrator, and Fmax are used on both channels.
However, input range and coupling are independent.
For cross channel phase, dual time and dual spectrum measurements, if the
collection specification is Overall and Spectrum or Overall Only, then the overall
value is calculated from the spectrum as an RSS overall. There is no support for
two channel analog overalls.
Triggerless Operation
Most two channel measurements use a trigger to establish running speed.
However, the running speed can be manually entered, or taken from a spectrum
by positioning the cursor on the 1X spectral peak.
Orbits typically require a trigger. If you don't define a trigger, the display shows a
random moving cursor around the trace and has no useful meaning. Therefore,
the cursor is not displayed when operating in triggerless mode with orbits. With
orbits, the specified rpm value is used to set both the Fmax and the frequency
used to configure the orbit input filters.
Set Up Cross Channel Phase Measurement Definitions in the Emonitor
Software
To set up the cross channel phase measurements in the Emonitor software, follow
these steps.
1. Select the machine that you want to set up cross channel phase
measurements.
2. In the Location pane, create the first location and set Lo. Channel to 1.
3. In the Measurement Definition pane, create the magnitude measurement
definition by setting Data Type to Magnitude.