Where machinery is designed on a modular basis so that it can be readily customised in production, a flexible automation solution is needed. An intelligent HMI can be the answer, giving operator visualisation plus control functionality. When that control is made through a powerful Soft-PLC with programming to IEC61131-3, there can be major cost advantages to the designer. Ideally suited are small or simple machines that require a touchscreen operator interface, and where the alternatives are a mini-PLC plus a HMI, or a full IPC with touchscreen.
Lenze have extended their proven EL100 range of touchscreen HMIs with the addition of an optional Soft-PLC. This brings together visualisation and machine control in a way that reduces machine build costs. The HMI element includes free software that allows production and control sequences to be set up in an easily comprehensible and individual way. In light of the rapid increase in both the number and variety of functions and tasks performed by modern machines, ergonomical design, machine and context-based menus as well as explanatory interfaces are becoming ever more important. With the support of functions such as soft keys, complex graphics and multiple languages, these HMIs can be adjusted to the most diverse fields of application via the software. Therefore this suits applications that are price sensitive and produced in small to medium numbers.
The heart of the EL100 series is a powerful XScale processor that can handle even the most complex of visualisation tasks. It is also very energy efficient, which allows it to run without a fan. And since no other moving parts are used - Flash and RAM or SD memory cards are used as the storage medium - the devices are particularly robust and reliable. Displays are TFT in sizes from 5.7 to 12.1 inches and 64K colours, 640 x 480 pixel resolution. An integrated real-time clock is fitted with a battery back-up rated for 7 years.
The Soft-PLC element of the device helps reduce costs by meeting the de facto industry standard IEC61131-3. Compared to the pure visualisation HMI’s, the PLC versions have twice as much memory (64MB Flash, 128MB RAM) and an additional, maintenance free GoldCap UPS for bridging brief power failures. This UPS ensures that all necessary variables are saved on the integrated Flash disc in the event of a supply loss or an emergency stop. This guarantees that the PLC can be set to a defined status ready for a restart, therefore it is not necessary to save the variables cyclically to a ‘slow’ memory and the controller can run faster.
Connectivity is an important factor to reduce costs in the control system. The EL100 HMI/PLCs include USB-A and USB-B interfaces which are well established in automation technology, allowing industrial communication with higher level PCs and also connection of additional devices, printers, keyboards or communication media. In addition to this, the basic equipment of the EL100-HMIs includes a serial interface (RS232). The SD card slot, which is located on the back of the device, allows SD cards of various capacities to be used. These memory cards replace conventional hard disks, which are prone to failure, and offer sufficient space for system, archive and formula data or other applications. An installed Ethernet interface can also be used to conveniently connect to other systems, such as higher-level engineering stations or industrial PCs.
When it comes to automation systems, the designer has to choose between integrating components from different manufacturers with the inevitable engineering time cost, or an automation platform from a single supplier. Lenze maximise the cost savings from the second of these options through fitting a CAN interface which is also the system bus for a range of L-force products. Thus the HMI/PLCs have a CAN interface that can communicate directly with servo and inverter drives, I/O and even higher level PCs. This system bus approach saves a large amount of engineering time during the installation and commissioning phases. In addition, as the CAN interfaces are standard in products, purchase costs are reduced too.
That the EL100 HMI/PLCs are remarkably cost-effective and easy-to-use is illustrated by the fact that visualistion software, PLC programming software and the Windows CE operating system are all included in the price. Windows CE offers real time capability and is a familiar and suitable platform for both control tasks and motion control. Unlike Windows XP, the Windows CE operating system used throughout the EL100 range does not require separate real-time extensions, which would take up additional memory. Thanks to its miniaturised architecture, the system is easily accommodated on a Flash memory card. This makes it a robust system that can be integrated into machines without the protection of panels, and with the additional benefit that cooling fans and hard disks are avoided. Users can choose between Windows CE 5.0 Core, or Windows CE 5.0 Professional Plus which has additional features such as a mouse indicator and file viewer.
The EL100 HMIs include visualistion software called VisiWinNET at no extra charge. With this system, OEMs and end-users are ideally equipped to handle current and future requirements. The supported visualisation functions include alarms and info messages and also formulae or trend charts. Even the engineering environment is based on tried-and-tested standards and uses the latest software technologies. It is open, flexible, powerful and future-proof. VisiWinNET therefore allows user-friendly interfaces to be created both quickly and simply. A project wizard supports project engineers when selecting the target hardware and provides a suitable basic configuration that can be freely adjusted for every project. The program supports import of system variables such as time or display brightness, which can then be used in the application. Alongside this, it is also possible to import the variables of the PLC program via an offline browser, while language selection also allows the use and combination of any languages.
In addition, VisiWinNET can - unlike a resource-consuming OPC solution - access the PLC variables directly using a driver without the need for the time-consuming settings of DCOM communication. Together with the network compatibility of the solution, this enables remote control and remote monitoring concepts to be implemented which also include the PLC functions.
New engineering products have to deliver benefits that can be equated to cost savings and the Lenze EL100 HMIs with PLC do exactly that for machines that need PLC control and touchscreen visualisation. Compared to a separate mini-PLC, they are cost effective because the single device gives both visualisation and control, saving engineering time. Similar to industrial PCs, they offer openness with the properties of an embedded system - robustness, stability and simplicity - with their uniform interfaces. A long- and trouble-free life is assured by the absence off cooling fans or other moving parts. These devices are easy to use with the familiar Windows CE operating system. In addition they are truly cost-effective with VisiWinNET visualisation software and IEC61131-3 programming software included in the price package.