Network Retrofit Eliminates Wiring Problems

To eliminate these shut downs, management choose Unique Automation, LLC (a Mitsubishi Distributor located near Rochester, NY), to replace the problematic CNC controllers and point to point wiring with a networked control system using Mitsubishi C64 CNC controllers, Q-Series automation controllers, and GOT operator interfaces, all tied together with the high-speed
CC-Link network protocol.

The IMASFLEX seven-station dial index machining center turns bar stock into automotive air conditioner manifolds.

CC-Link (Control & Communication Link) is an industrial automation network that processes both control and information data at high speed. Originally developed by Mitsubishi Electric, it is an open technology field-level network that provides high speed, deterministic communication linking a range of automation devices over a single cable. 

The upgraded machining center consists of seven machining stations, each with an X, Y and Z-Axis as well as a spindle control. Operators use an eighth station for loading and unloading.

The Q-Series Automation Controller is connected to two CC-Link Master stations to control two independent CC-Link networks. The first network includes four C64 controllers to manage the seven machining stations within the IMASFLEX machine.  It serves a total of 28 axes of movement, handling over 1000 I/O points that communicate status to the controllers as well as transmit commands to control other functions of the machine.

A portion of the original central control panel shows some of the wiring that was eliminated.

The second network consists of 24 Mitsubishi Remote I/O modules to handle more than 600 inputs and outputs on the machining center. These I/O consist of operator push buttons and selector switches for machine operation, pneumatic valve manifolds to control tool and part manipulations, tool changer inputs, over-travel and home switches, cooling pumps and valves, lubrication systems, hydraulic systems, and chip removal and filtration systems.

The control program reads all inputs and outputs on the second network, and communicates necessary information to the four controllers on the first network. Each of the four controllers executes 7,500 steps of ladder code for a total of 30,000 steps. The total processing time for this entire control loop is approximately 7.3 ms, which is a significant improvement over the
previous system.

With the CC-Link network, more than 25,000 feet of wiring was eliminated per machine. The network links the remote I/O stations to the Q-Series automation controller and GOT operator interfaces.

A CC-Link Remote I/O Station located at one of the seven machining stations helps eliminate the need to route individual I/O wiring back to a central control panel.

The first IMASFLEX retrofit has been operating for more than a year without a control system failure. T&L Automatics was able to cancel the maintenance contract with the original control manufacturer, saving tens of thousands of dollars in annual maintenance fees. In addition, production productivity increased by 20%. Quality of the machined parts has improved, enabling T&L to maintain tolerances right-on-center. And diagnosing machine mechanical problems and adding new I/O points is far easier and much faster due to CC-Link network.

CC-Link networking and Mitsubishi controls have proven so reliable and cost effective that two more IMASFLEX machining centers and one Liberty machine will be retrofitted with these systems within the next year. A fourth IMASFLEX will be retrofitted next year.

CC-Link America,
cclinkamerica.org