The main benefits to the user are faster processing and more memory, which translate into quicker screen refreshes, but there are more enhancements that mean the PMIs are easier and quicker to integrate into machinery or process equipment.
With 400MHz XScale PXA255 processors, the speed of the third-generation PMIs is double that of the second-generation, and SDRAM memory is now upgradeable from 64MB to 128MB if required - in addition to the standard 32MB of Flash memory. The operating system is also Windows CE.Net version 4.2 instead of CE 3.0, and an RJ45 10/100 MBit/s Fast Ethernet connection is installed on all units in the new range (a second Ethernet interface is offered as an option).
More USB connections are provided (two or four hosts and one slave, against one host USB port on the previous generation), and all models feature a variety of other ports, such as a PCMCIA slot (for two Type II or one Type III card), a PC/104 expansion slot, a PS/2 input, COM1 (RS-232), COM2 (RS-232/422/485 switchable), an audio line out and an optional parallel port.
Another development that will be welcomed by many machine builders and system integrators is the move from using external fieldbus adapters to pre-installed internal modules. This will speed integration and save valuable cabinet space.
As before, customers can either choose the PMIopen version, which comes with just the operating system installed, or the PMIvisu version that benefits from the Pilz PMI-PRO runtime software. Those purchasing the PMIopen models can, of course, load any software compatible with Windows CE.NET 4.0, and Pilz has already successfully tested three SCADA packages: zenOn from COPA-DATA, Web Studio from InduSoft and Movicon from Progea.
One of the advantages of the PMI range is its versatility. Five different display sizes are offered as follows:
- PMI 315: 5.7in, 320 x 240 pixels, QVGA and 256 colours
- PMI 316: 6.5in, 640 x 480 pixels, VGA and 65, 536 colours
- PMI 326: 10.4in, 640 x 480 pixels, VGA and 65, 536 colours
- PMI 331: 12.1in, 800 x 600 pixels, XVGA and 65, 536 colours
- PMI 338: 15in, 1024 x 768 pixels, XVGA and 65, 536 colours
While the smallest model uses LCD (CSTN) technology, the others use LCD (TFT) technology. All have analogue-resistive touchscreens, and clear self-adhesive membranes are available to provide additional protection against damage to the screen from dirt, pens and other objects.
As before, the third-generation PMI range has IP65 sealing, but a new development is the option to have the front panel customised for OEMs or customers ordering larger volumes.