Rockwell Automation 1440-VLF02-01RA XM-121 Absolute Shaft Module - Manual (Page 150)

Publication GMSI10-UM014D-EN-P - May 2010
Glossary 142
online help
Online help allows you to get help for your program on the computer screen
by pressing F1. The help that appears in the Help window is context sensitive,
which means that the help is related to what you are currently doing in the
program.
orders
Multiples of the operating speed of a piece of equipment. The first order is the
operating speed. The second order is two times the operating speed, and so
on.
Polled
DeviceNet communications method in which module sends data in response
to a poll request from a master device.
Program mode
The XM module is idle. Typically this occurs when the module configuration
settings are being updated with the XM Configuration program. In Program
mode, the signal processing/measurement process is stopped. The status of
the alarms is set to the disarm state to prevent a false alert or danger status.
Run mode
In Run mode, the module collects measurement data and monitors each
measurement device.
settling time
The amount of time it takes a measurement to reach 90% of the final value
given a step change in the input signal.
Shaft Absolute
Shaft Absolute is the measurement of the shaft’s motion relative to free space
(its absolute motion). Shaft Absolute can be measured two ways. The first
method, which is used by the XM-121A, is to electronically sum the signals of
both a eddy current probe measuring shaft vibration relative to the case, and
an acceleration or velocity sensor mounted on the casing measuring case
absolute vibration. The second method is to use a shaft rider, which is a spring
mounted device that physically rides on the surface of the shaft, normally a
velocity sensor mounted on top of the shaft rider.
signal detection
Defines the method of conditioning or measuring a dynamic input signal. Peak
(0 to the peak voltage), Peak-Peak (minimum peak to maximum peak), and