R. STAHL Offers User-Replaceable Modules in Hazardous Areas
20 May 2008
Unlike comparable products, panel PCs of R. STAHL HMI Systems' Open HMI series consist of modules with individual explosion-protection. Users with appropriate training may therefore open the devices for maintenance purposes or to replace individual parts. To date, panel PCs in hazardous areas usually had to be replaced completely (in the case of explosion protection type Ex m) or could only be repaired and re-assembled under controlled conditions (e.g. in the case of Ex q).
In the case of the Open HMI series, each module has its individual, ideally suited type of explosion protection. Some brief training suffices for users to carry out many service and maintenance tasks on their own. This is a marked improvement on the cumbersome handling of explosion-protected devices that used to be necessary.
Some modules are of protection type Ex m (casting compound protection), others, such as the CPU and the power supply unit, are of protection type Ex d, and the connection PCB's are of protection type Ex e or I.S. A terminal box with increased safety Ex e provides connections for hard disks (available with a capacity of up to 120GB) or USB 2.0 flash drives (available in sizes up to 16GB), making the replacement of these bulk memory drives particularly easy.
The HMIs' casing remains light and requires no particular certification. In mechanical terms, the HMIs (certified by many international certification authorities) can withstand even extreme ambient conditions, such as can be found in the oil and gas industries.
