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and low-voltage instrumenta-

Fig. 4. Each lightning protec- tion and control. Others may tion solution is tailored to the structure’s need, note DAS on require a no-strike system top of the drilling tower.

that will provide security against lightning strikes on the helipad, drill derrick, or jackup legs (Fig. 4).

In implementing these solutions, engineers work to improve the level of safety for the workforce, protect the vessels and facilities against direct strikes, as well as secondary surges, reduce

The system currently has over a 99% downtime and associated costs, and reliability rate. extend facility life through preventa-

Of course, the potential danger isn’t tive measures. Protecting a vessel from only from direct strikes. Secondary lightning strikes also works to protect surges also wreak havoc on electrical systems that otherwise would have instruments and equipment and pro- lost a considerable portion of their tecting this sophisticated equipment lifespan. In today’s uncertain economy, is a concern in the energy industry. many companies are looking for cost-

Dynamic positioning, drilling instru- effective protection as a way to extend mentation, and other rig management the lives of older vessels and work systems are essential to the facility toward being more risk averse with staying online, and are vulnerable to new construction.

lightning effects. Systems that work The reliability rate of over 99% to prevent, rather than attract, light- comes from data from over 3,500 ning take these secondary surges into systems. Results like these have led account as well. to some of the world’s largest offshore

The meantime-between-failure for producers to look into protecting sensitive systems is an important con- themselves from the negative effects sideration in damage mitigation and of lightning, providing a critical safety loss calculation. The voltage needed to net for their equipment, personnel, and run instrumentation controls decreases bottom line. as the systems become smarter and more effcient, although they become

FURTHER READING more intricate and vulnerable. The risk of a high-end secondary surge damag- Drabkin, M., Mui, C., Ong L.; Lightning ing equipment and affecting the opera- Protection of Tall Structures, 2012 tions also rises. Because not every International Conference on Lightning case is the same, work with offshore Protection; Vienna, Austria; September rigs and platforms begins with a risk 2-7, 2012.

assessment. LEC engineers interview key personnel, review schematics and Peter Carpenter has wiring diagrams, and inspect in situ more than 26 years grounding practices. Last year, vulner- experience in elec- ability studies based on International tronic engineering

Electrotechnical Commission (IEC) and and lightning protec-

National Fire Protection Association tion. Since 1988, he (NFPA) guidelines and standards has been the director resulted in solutions for nearly a dozen of applied engineering at Lightning companies’ offshore platforms and rigs. Eliminators and Consultants. He has

Each lightning protection solution assisted in many feld evaluations to can be different as well, tailored to solve past bonding, grounding, power specifc needs revealed in these site conditioning, and lightning-related surveys. Some rigs may only need surge electronic failures. Carpenter studied protection devices, which have become electrical engineering technology at critical to protecting power distribution Cerritos College, Norwalk, California. oedigital.com October 2013 | OE 51 048_OE1013_EPIC3_Lightning.indd 51 9/29/13 9:56 PM