The use of desktop PCs is widespread in industrial manufacturing areas. For hazardous areas, this requires special attention. While Ex protected PCs are available, prices are high and the choice of specifications is limited.
So using a standard model makes sense, provided a suitable Ex protection method can be applied. Ex p (Purge & Pressurisation) provides a flexible and cost-effective solution.
The PC and monitor are installed inside an Ex p stainless steel enclosure fitted with a suitable purge system. The monitor is visible through the glazed window. As the keyboard forms part of the enclosure wall it must be suitably Ex certified. Expo can supply pressurised or Intrinsically Safe (IS) keyboards.
The enclosure dimensions can be tailor-made for the system to be used. Ex approved cable glands are fitted for incoming power and ethernet. Within the confines of the enclosure, the PC and monitor may get warm, so consideration should be given to the use of a vortex cooler. The enclosure can be supplied on a plinth or for table-top use.
In most cases Expo can certify the completed system, significantly reducing the overall project timescale.
For Zone 1 / Class 1 Div 1 applications, in addition to the use of an X purge, a mini purge interface unit (MIU) may be required to provide local isolation of both the power supply to the PC & monitor as well as incoming data lines such as ethernet.