Page 6 - Industrial Technology EXTRA 8th February 2021

spare parts or replacement equipment from Ian Patterson, Key Account Manager at
Reliance, as the company no longer exists. Mitsubishi Electric, adds: “Sometimes we faced
With support from the original control system gaps or inconsistent details about the movement of
provider not an option, Unipres turned to Mitsubishi each axis. For example, the existing documentation
Electric and local factory automation integration on press feed speed was not accurate enough. We
company AR Controls for advice with a view to were able to address this issue by making the
recommending a viable upgrade solution. The system flexible in controlling the speed while
companies all have a longstanding relationship that ensuring that this would not have any impact on the
dates back to when the Unipres plant in Sunderland mechanical components of the transfer press.”
was built, so AR Controls was familiar with the Another challenge consisted of completing the
factory and were able to quickly take stock of the upgrade without affecting the whole plant uptime.
issues the equipment was causing. Advanced simulations and offline testing were used
to assess and adjust the new motion control system.
Legacy control system More precisely, the project greatly benefitted from
The upgrade was particularly challenging, due to the Mitsubishi Electric’s simulation tool to evaluate
complexity of the transfer press and the need to software performance in combination with a full-
thoroughly understand the existing control system. As size mechanical test rig built by AR Controls.
Mike Dickinson, Business Development Manager at
AR Controls explains: “Unipres’ old solution was not Automation for better control
a particularly common system and there aren’t many The resulting motion control system for Unipres’
specialists around that have experience with it.” transfer press combines Mitsubishi Electric’s PLCs,
A substantial portion of the project consisted in servos and HMIs. To control the multi-axis
reverse-engineering all the functions offered by the operations of the transfer press in its de-stacking,
legacy motion control system as well as what pressing and transfer activities, three Q series PLCs
parameters were being regulated. As sometimes key were selected. These are often installed in similar
data or pieces of information were missing, we had applications due to their high speed and accuracy
to create a resilient system that would be able to as well as the ability to handle large volumes of
handle any variables.” data. The controllers are networked together as well
as with MR-J4-DU servos to regulate
the process. Each PLC is also linked to
its own GOT2000 HMI to deliver
visibility and diagnostic tools.
In addition, the project features the
first application in the country for
Mitsubishi Electric’s MR-CV power
regeneration converter unit. This is
connected to the servos to recover
braking energy from the servo axis and
feed it to the mains supply. This
innovative solution replaces the brake
resistors that were previously in use.

February 2021 • INDUSTRIAL TECHNOLOGY EXTRA • p6