SERVO CONTROLS UPGRADE
Allied Controls LLC's customer had an old GV3000 Reliance Electric A-C drive that failed, and the parts were no longer available for repair. This A-C drive controlled a 30 HP induction motor that included an encoder for feedback. The positioning was being controlled by an old Reliance Electric QUIQ positioning module that interfaced with relay logic to control the feeder.
Allied Controls LLC proposed an Allen Bradley solution using a Kinetix 5700 drive and a CompactLogix-L27 processor. This solution had a cost savings of using the existing 30 HP motor and encoder that were already in place.
Unfortunately for our customer, this machine was down, and the project had to be done on an accelerated schedule. A PO was received late Friday afternoon. All parts were ordered and were couriered to the customer's manufacturing facility. Saturday, our engineer did the electrical AutoCAD drawings while another engineer started programming changes.
On Sunday, Allied Controls LLC's technician arrived to start the installation. The old GV3000 Reliance Electric drive and Reliance Electric QUIQ positioning module were removed from the existing control panel. We installed a new CompactLogix PLC, and a Kinetix 5700 servo drive into the existing enclosure. A 6" PanelView Plus was added to communicate with the PLC and servo drive. The new PanelView allowed the operator to change servo speeds and distances. The PanelView also provided diagnostic information and alarms for the system.
The installation was completed on Monday morning, and an Allied Controls LLC engineer arrived to do I/O checkout and program debugging. By Wednesday morning, the program was debugged, and the customer started running production on the 600-ton press.
The original press feeder controls used a variable frequency drive with a large brake to control the position of the feeder. This required the system to come to a very sudden stop for every position move. The new servo drive was able to run the existing three-phase motor with servo commands. The new servo drive moves by ramping up speeds then ramping down speeds to stop in the correct position. This ramp-down is much easier on the machine and still quick enough that it does not affect cycle time.
The customer was very happy with the quick support and solution provided by Allied Controls LLC. Fourteen months after the first controls upgrade, the customer had another press feeder go down. We installed a similar solution on the 400-ton press feeder. The second solution involved an Allen Bradley Kinetix 5500 drive to control the existing servo motor on this press feeder.