Mini8 Loop Controller V5.04 Major Product Update

Eurotherm by Schneider ElectricTM is pleased to announce the release of the re-engineered Mini8® loop controller with a new firmware version, V5.04. This release provides many enhancements, while retaining the best-selling features our customers love.

Originally released in 2004, the Mini8 has become Eurotherm’s biggest selling PID controller offer.

Key benefits include:

  • Reliable, repeatable, precision control, meeting accuracy requirements of AMS2750F and CQI-9
  • Modular I/O
  • Focus on analog excellence
  • Physically compact, saving enclosure space
  • IEC 61131 function block wiring for flexible applications, simple or complex
  • Industry 4.0 ready, with a choice of communications options for machine connectivity

Now with the latest generation of high-performance control with autotune to minimize commissioning and engineering time, the new Mini8 adds significant improvements:

  • More processing power, more wires and function blocks, and faster communications
  • Up to 24 loops can be handled in a single box, using Ethernet communications and remote I/O
  • State-of-the-art “SuperLoop” function blocks, combining single loop PID and cascade control modes with full autotune
  • Native Ethernet and fully isolated EIA-485 serial Modbus RTU
  • Battery-free design reduces environmental impact and eradicates the need for periodic battery replacement
  • Re-engineered around IIoT and cybersecurity best practices to support “defense in depth” strategies
  • Form/Fit compatible with existing Mini8. No changes needed to drawings or wiring
  • High levels of backwards compatibility for applications and an automated application translation tool

Future releases planned for 2022 include native EtherCAT® server with full ETG.5003.2060 temperature controller support for semiconductor fabrication equipment, and a ramp/soak programmer.

Ordering the new Mini8

To order the new Mini8, select one of the Field 1 options with an “E” suffix. These are equivalent to the non-suffixed codes used by the older variant, for example “ACQ”, “4LP”, etc.

For the closest compatibility with the older Mini8, users may select “LEG” for “Legacy” in Field 10 to provide the older Eurotherm control algorithm function block. However, the Legacy loop function block does not provide the benefits of the SuperLoop control blocks. Eurotherm recommends use of the SuperLoop for all new applications.

In most cases applications will be able to be directly transitioned to the new Mini8 using the iTools translation tool, and the translation process is needed even for Legacy or Superloops alike.

The remainder of the order code for new Mini8 is very similar to the old Mini8. Additional wires and loops are available, there is a different set of communications options, and a new “Configuration Lock” function via field 19. This was previously known as “OEM Security” and available via EU0725 in the specials field. This function is provided to hide configuration information behind a password protected lock, to help guard against intellectual property transfer.

Note that where the “MODBUS” serial Modbus RTU communications was previously used, the “ISOLMBUS” should now be chosen. This is functionally equivalent.

What are SuperLoops?

“SuperLoops” are the current state of the art Eurotherm PID control function blocks. They provide a superset of control modes, including PID, On-Off, and Cascade via a single soft wiring interface.

In single loop mode, the SuperLoop provides control performance as available in the EPC3000 Programmable Controllers. The Mini8 I/O structure can support up to sixteen SuperLoops.

If “Cascade” is purchased, the Mini8 can support up to eight loops in Cascade mode. It is possible to mix and match modes, such that two loops may be Cascade, and up to twelve single loops, using Mini8 physical I/O.

An additional eight SuperLoops available for use with remote I/O with input and output values provided using Ethernet communications. An analog input is required as the process input, and an analog output value will be generated to be applied to the output device. Time proportioned digital outputs are not generated. This is intended for some specific applications where low precision loops are required, with a PLC generating the inputs and pulse-width modulation (PWM) or analog signal for the outputs.

Transitioning from the old to the new Mini8 variant

The existing model is expected to remain available until Q3 2022, to allow time for customers to validate their applications and migrate to the newer model.

Eurotherm supply of the older Mini8 variant is constrained, since parts are now difficult to obtain. This is likely to be reflected by increased prices, and eventually limited supply as key customers are given preference where transition has not been possible.

Transitioning early will help assure continuity of supply, and reduce the impact of price increases.

Some existing functions will not be available in the first release of the new Mini8, with some others discontinued. Please see below:

1) Real time clock. The real time clock requires a battery to maintain the time when the unit is unpowered. This is also used in existing Mini8 to retain the serial number and configuration data – once the battery expires, it requires replacement which must be done in an approved Eurotherm service centre on an approximately 7-year cycle, including units in stores used for spares. If the battery is not replaced in time and loses function, serial numbers and configuration data are lost when mains power is next disconnected. The lithium battery technology is problematic from the point of view of transport and environmental impact. We are therefore taking this opportunity to remove it from the product, replacing the serial number and configuration storage with non-volatile FRAM memory.

Therefore, the real time clock related functions (Alarm Log, Timed Events) in Mini8 will not be available in the new variant.

2) Profibus DP. Usage of Profibus DP is very low, and we are building our digital communications strategy for new products around Ethernet protocols. We will not be supporting Profibus DP in the new Mini8 release. Provision of Profinet – the Ethernet based replacement for Profibus DP - is under review but not yet planned.

3) EtherNet/IP. Usage of EtherNet/IP is currently low, and at this time we are not planning to include it in the new variant. However this may be provided later if there is sufficient validated demand for it.

4) Non-isolated Serial Communications. There are two options for serial communication hardware in the existing Mini8: isolated and non-isolated. The vast majority of existing applications use the non-isolated version, as the list price is slightly lower. However, this creates some risks of electromagnetic interference (EMI), particularly with the new higher performance microprocessor, and so we will be discontinuing the non-isolated option. We have adjusted the list price of the isolated option so the cost impact is neutral.

We will be mandating that the point-to-point communication via the RJ11 configuration connector is not used in applications, for example for panel connections or I/O. This connection is non-isolated and creates potential
for EMI risks.

Our strong recommendation is that users migrate where possible to Ethernet based protocols that support multiple connections on the same cable and will generally be of a similar list price to the lower performance serial communications.

5) EtherCAT. The new Mini8 variant will contain fully integrated EtherCAT, expected to be available Q3 2022. This will replace the existing EtherCAT interface. The existing interface will not be available in the new variant Mini8 during the gap between the first Mini8 release and later release of the integrated EtherCAT protocol, so the existing Mini8 model should be used in EtherCAT applications until then. The new EtherCAT protocol will meet the requirements of ETG.5003.2060 temperature controller profile for semiconductor fabrication equipment.

6) Changes to Function Blocks. There will be various changes to the function block library, reflecting the current and enhanced Eurotherm control library. Generally, equivalent functions are available.

Most significantly:

  1. LIN16 block will be replaced with the new LIN32 block.
  2. The Zirconia block will be removed, since Mini8 hardware has never supported Zirconia probe compatible high impedance inputs and will not be developed further to do so.
  3. Removal of Analog and Digital Alarm blocks, to be replaced with the “Generic” Alarm block as found in EPC3000 programmable controllers. All existing alarm types and modes remain available.
  4. Removal of the Load Simulation function block. There are minor differences with the communications and instrument blocks, with changes to parameterization and the logical presentation of information.
  5. Sub-assemblies. Communications boards, PSU, and microprocessor sub-assemblies will not be available in the new variant Mini8. I/O Modules will be available.
  6. EC8 and FC8 Options. These options provide an 8-loop extrusion and furnace controller respectively, and will be discontinued due to very low usage.
  7. The ramp/soak programmer is not available in the first release. It is expected to be available in a later release during 2022, and is planned to be identical to the existing Mini8 programmer.

Launch and Supporting Documentation

The full launch of the re-engineered Mini8 will take place when the EtherCAT communications option and Programmer are released, expected to be before Q3 2022. This will include product brochure, sales presentations, battlecards, and
other material.

In the meantime, please refer to the new Mini8 microsite at: where you will find information, a video, and a datasheet. Customers and prospective customers should be directed to this page where they may sign up for further information.

It is important because of the limited forward availability of the existing Mini8 that any customers using the offer are informed as soon as possible of the new variant.

Some technical training sessions will be arranged for early February, 2022, covering the differences between the old and new variants, and the operation of the application translation tool in iTools.

Itools Support

V5.04 is supported by iTools V9.85. This may be downloaded from: