Distributed I/O for Food Equipment

Product customization

Peerless Machinery Corporation’s Peerless provides integrated systems for its customers, such as dough handling systems that move dough from the mixer to make-up and forming equipment.

The first obstacle Peerless faced was standardizing on a network protocol that would synchronize all systems in order for them to operate in tandem. EtherNet/IP was the network protocol that Peerless chose to use because it provides tighter control and helped Peerless streamline operations. “We see EtherNet/IP as the emerging standard, as it is gaining worldwide acceptance in the industrial sector,” says Eric Cruse, Controls Engineer with Peerless. “We also wanted a system that would allow expansion of diagnostic information and provide an open platform for our customers.” Although implementing EtherNet/IP gave the company tighter control, Peerless still had a centralized cabinet full of drives and PLCs, and was running lines of conduit with hard-wired cables from its machines to the controllers. Because of the layout of the plant floor, the lines of conduit can be up to 250 feet long, and are sometimes routed to a different floor in the plant altogether.

Another challenge for the company is maintaining a clean manufacturing environment without harming the components that keep the plant up and running. Since all of Peerless’ applications are used in the food industry, it is imperative that the machines remain sanitary. High pressure, high temperature washdowns, often using harsh cleaning agents, are necessary to maintain a sterile working environment.

Implementing standard I/O

To address these issues, Peerless chose to implement distributed I/O to remove the main control panel away from the potentially harsh environment. The company accomplished this by creating substations on each machine using Turck USA’s BL20 EtherNet/IP terminal-wired I/O. BL 20 is an IP 20-rated I/O designed for cabinet installation, and provides the company with the local control it needs on the plant floor without the primary control panel. “We chose to use Turck’s BL20 line because it’s easy to troubleshoot at the machine,” adds Cruse. Peerless also uses Turck NEMA4X rated junction boxes within the distributed I/O structure, and runs all localized sensors and other equipment through these boxes.

Each substation contains one BL20 system that maintains control for one machine, and utilizes Turck fully connectorized cordsets to transfer information from the substation to the main control cabinet. By doing this, Peerless no longer needs to run long lines of conduit and hard-wire each machine to the main control cabinet. “Converting to distributed I/O has cut in-plant installation time in half,” adds Cruse.