Customised UPS systems for offshore rig hazardous areas
3 July 2014
R. STAHL plans and implements individual, application-specific uninterruptible power supply (UPS) systems for oil and gas rigs and similar applications with hazardous areas where 100% availability is imperative. On unmanned platforms in particular, these systems ensure that crucial equipment (e.g. valves, pumps, navigation and signal technology such as GPS and flashing beacons) continues to be operational for a defined period of time in case of an overall power failure. This enables users to retrieve and store data in a coordinated fashion before bringing the platform into a safe state. Based on a versatile modular portfolio, R. STAHL designs UPS solutions exactly according to customer specifications. These systems can be delivered as turn-key package units on request. Thanks to decades of experience in the field and extensive explosion-protection know-how, R. STAHL is able to pursue a comprehensive engineering approach that starts with the choice of components. Optimal configurations can yield complex positive synergy effects in the project planning stage. Other suppliers of hazardous area solutions often only choose to put conventional UPS systems in special enclosures in order to formally safeguard explosion protection.
In a recent project, R. STAHL e.g. supplied a custom-engineered compact DC UPS system for Ex zone 1 that was installed on an offshore platform off the coast of Gabon in Central Africa. This system is equipped with robust, corrosion-proof CUBEx housings manufactured from copper-free cast aluminium that are designed for extreme environments. In this case, they withstand temperatures up to +50 °C. The UPS provides up to 4,000 W in operation and includes NiCd batteries with a 300 Ah capacity in an Ex e battery container, a central control module with all required specification- and standard-compliant UPS components, and a DC energy distribution board to protect the connected loads. Redundant charging technology is an integral part of the enclosed system, which achieves excellent thermal power loss management with reliable dissipation from the pressurised chamber. The UPS features a software-free design and contains no rotating parts like fans. Temperature-compensated charging, power diodes for voltage adjustment, and Ex LEDs to display the UPS status ensure very reliable operation and excellent safety. R. STAHL’s integrated Ex UPS guard monitors the standard-compliant operation of the system according to EN 60079 ff.