Wireless HMI is `first with safety`
Siemens claims to have produced the first wireless HMI device to incorporate safety functions. Its Simatic Mobile Panel 277 has two enabling buttons and an emergency-stop button, and the safety functions are certified to SIL3.
When the HMI is being configured (using Windows-based software), users can define the "effective range" of the wireless transmissions, outside of which it will not communicate. This ensures that then appropriate operating screens are shown on the 7.5-inch touchscreen, and the appropriate operator authorisations apply, anywhere in a plant. The zones can be defined so that functions such as operator authorisations and displays apply automatically when the HMI is brought into a zone.
The IP65-protected HMI (shown above) is designed to withstand a drop from 1.2m. The device has 18 membrane keys and 6Mb of memory, which can be supplemented using plug-in memory cards to store recipes and other data. Versions are available without the safety functions.
