With the Ex p x621 control and monitoring system R. STAHL presents an innovative modular solution for easier construction of pressurised control panels with Ex p type of protection. While conventional systems for a range of panel sizes and construction types use a wide range of dedicated devices, R. STAHL has reduced this complexity to three basic components in uniform versions for its new system solution. The combination of an Ex p control unit, Ex p pressure monitors that simultaneously also function as pressure outlets, and Ex p purge valves with digital and proportional control is able to meet all requirements, from very small enclosures with a volume of 10 l to Ex p control cabinets with volumes of 4000 l.
Cost-effective continuous operation
In this way, the Ex p controller makes control processes available for all control cabinet sizes and enables them to be adjusted easily to meet users' requirements. If, for instance, the purge pressure or purge time needs to be reduced for larger control panels, all it takes is the installation of additional Ex p pressure monitors. The use of a suitable number of a single pressure monitor variant reduces expenditure and work for both engineering and storage. The outstanding precision of the pressure sensors used also enables operation close to the pressure switch-off threshold, which keeps leakage to a minimum and enables extremely cost-effective continuous operation. The purge valve control, which is also integrated in the control unit, further simplifies the process in either digital or proportional mode.
Moreover, effective Ex p vortex air coolers are available for cooling Ex p cabinets, the cooling power of which can be scaled by installing additional structurally identical versions, in accordance with the same simple principle that applies to pressure monitors. The Ex p bypass circuit on the control unit, in which the electronics operate intrinsically safely, significantly reduces the required expenditure for inspection and maintenance work. The new commissioning process eliminates the need for costly test steps after maintenance and retrofitting work and guarantees explosion protection at all times.
The certified monitoring system for control panels, is used in Ex Zone 1/21 in accordance with IEC/EN/DIN 60079-2 as a redundant version and in Ex Zone 2/22 as a more cost-effective simple version. The compact design of the components and the state-of-the-art operating interface of the Ex p controller enable space-saving installation and easy commissioning. Due to the external mounting of the slim Ex p control unit on the control panel side wall, the full installation volume is reserved for the application. The Ex p control unit made of resistant glass-fiber reinforced polyester is available with or without viewing window.
ACHEMA 2022 Exhibitor Hall 11.1, C45