new firmware release, PACMotion 1.5,
expands the feature set in GE Intelligent Platforms' RX3i PAC products. The new
software enhancements include two axis of analog servo control, cam
capabilities that target applications such as web handling, and more flexible
diagnostic tools that increase operator productivity.
"A key addition is two axes of analog control
which provides more capabilities for applications such as a custom linear
actuator, linear motor or specialty device," says Paul Derstine, product manager
for GE Intelligent Platforms' Control and Communications Systems. "This new
version will allow users to connect a much broader range of devices. There are
times when a custom motor, linear actuator or linear hydraulic servo valve is
required in an application. At other times in a machine retrofit, the servos
are already in place and do not need to be replaced."
The two-axis analog servo control feature
allows control of one or two third-party amplifiers using a 10V dc analog speed
or torque command. And since a PACMotion module controls four axes, each module
can use two of those axes for third-party servos. Mixing FANUC and analog axes
on the same PACMotion module is supported.
The release also includes new cam
enhancements for applications where there are a large number of synchronized
axes connected via a mechanical interface such as web handling applications. When
a series of rolls are linked together through gearing and electronic cams, for
example, the software provides an ability to align all of the slave axes on the
profile before the master actually starts moving.
Enhancements to the cam functionality create
tighter synchronization of axes. A Cam Load-Data feature allows exact
positioning of all slave axes, relative to the current position of the master,
prior to machine start-up rather than having to ramp slave axes to synchronize
with the master once it is moving. Ensuring precise synchronization reduces
product scrap at the beginning of a production run and can improve production
A new Cam Exit Distance feature enhances the
flexibility of the cam feature by allowing for controlled exiting of a cam
profile at a predetermined master position along the profile path. Exiting a
cam before the end of the profile provides greater dynamic control flexibility
to respond to machine or line events such as a jam or product changeover
preventing additional product loss of production down time.
According to Derstine, another
important diagnostic feature chronologically logs any events such as errors or
warnings on the module in a FIFO queue. In order to get access to that
information, it required a PC and our machine edition software to view the
event queue log file. Customers wanted the machine operator to have access to that,
so we now have made the top 10, most recent events available programmatically
to the operator, he says.
Program access to the event queue provides
the operator with the ability to obtain diagnostic/troubleshooting information
on the operator interface. Because customers need access to the most recent
sequence of events/errors rather than the last axis or module error, this
enhancement allows users to access the event queue data right within the
program, without the need of accessing the data via Proficyฎ
Edition on a personal computer.
The chronological sequence of the events is
preserved, aiding users in determining the exact sequence of events leading up
to an error or machine shutdown. Access to such real-time sequential event data
enables faster diagnosis of machine or line stoppages yielding increased
machine uptime and enhanced productivity.
"PACMotion has been designed with performance
in mind and we use a co-processor for the path planning function for all axes
of motion," says Derstine. "Users can add axes in the system without changing
cycle times or impacting the scan rate in the PLC program which helps squeeze
performance out of the application."