Eurotherm EPC2000 Programmable Controllers

Real World Applications

Muffle Furnace With Touchscreen HMI

A muffle furnace separates the workpiece from the heat source by means of a “muffle”, a removable and sometimes adjustable component used to aid temperature uniformity.

The furnaces may be used for heat treatment of small components and laboratory testing of materials, and many other applications where uniformity and accuracy of temperature control is required.

In this example, the Eurotherm EPC2000 device provides high accuracy temperature control, using the Eurotherm EPack™ SCR Power controller to manage the non-linear heating characteristics of the loads. A Pro-face GP4100 touchscreen is used as the primary operator interface.

This provides a high performance furnace control system with fast responding enhanced Eurotherm PID control with minimal overshoot. The touchscreen panel is easy-to-use and customize, and the furnace can be connected using Ethernet communication or via a WiFi router to data loggers or personal computers.

Baking Oven With Distributed Zones

Commercial biscuit or baking ovens are often arranged in long tunnels, through which the product being processed travels on a conveyor. They are usually gas fired, and made up of separate zones. Typically a PLC and drive system is used to control the conveyor.

Accurate temperature control in each zone is essential to reduce wastage normally due to under or over-baking. The ovens may be many meters in length, and running cabling the length of the machine can be expensive.

Using EPC2000 devices distributed along the machine allows each controller to be placed near to the point of use, reducing cable runs and maintaining operating temperature even if the PLC is offline.

Semiconductor Etch Processes

The etching process is used to remove surface layers from a wafer during semiconductor fabrication. It is a critically important part of the manufacturing process and each wafer will undergo multiple etching steps.

Successful etching relies on forming a high uniformity cavity in the surface using a combination of chemistry and precise control of temperature. As die sizes shrink, the performance of the temperature control system becomes increasingly important for yield. Wafers have a limited tolerance to temperature fluctuations during the full fabrication cycle, and it is important in each process step to minimize temperature variation.

The EPC2000 controller is a highly versatile and cost effective solution offering high stability precision measurement and control with Ethernet connectivity.

Post Weld Heat Treatment (PWHT) of Pipes

Post weld heat treatment is a method of reducing residual stresses in welded joints. Joints are wrapped in ceramic pad heating elements and heated according to a specific ramp/soak sequence, often applied across multiple heating zones simultaneously.

EPC2000 controllers provide a cost-effective method of clustering multiple single loops in a compact console built into a portable trolley.

One unit is configured as a master programmer, broadcasting a setpoint to several slave units. Each slave uses a deviation alarm relay to close a digital input on the master unit if it has not yet approached setpoint, to provide a holdback or “guaranteed soak” function in each zone.

Using the recipe function on the EPC2000 instrument, units can be easily reconfigured with a digital input, permitting a console to be subdivided into switchable sets running different profiles at the same time for separate operations.