Case studies(Introduction examples)

Lightning protection for buildings and structures

Lightning risk is high with networking.

As offices become more networked and equipment more precise, the risk of lightning is increasing, and OTOWA considers and proposes lightning countermeasures for the entire facility. OTOWA considers and proposes lightning countermeasures for the entire facility. It is important to consider lightning countermeasures for the building itself and lightning surge countermeasures for electrical equipment in total, rather than separately. Total lightning countermeasures vary depending on various conditions such as the location of the building and electrical wiring. By examining lightning countermeasures from various perspectives, we can design more optimal lightning countermeasures.

Lightning countermeasures are part of risk management.
OTOWA will propose the best lightning countermeasure by comparing the risk of lightning and the cost of the countermeasure.

Dangers if no measures are taken
  • Interruption of corporate activities due to breakdowns or problems with various facilities, and loss of opportunities until recovery
  • Loss of social trust in the company due to business interruption

Lightning protection points for buildings and structures

Countermeasure points
The rooftop and bottom floor of the building, the electric power intake area, and the telephone line intake area are affected by direct lightning surges (LPZ1), so SPDs (Class I, Category D1) are installed to deal with direct lightning surges. The middle floor is affected by induced lightning surge (LPZ2), so SPD (Class II, Category C2) should be installed to cope with induced lightning surge. It is effective to install SPD for power supply on each floor or each distribution panel.

In particular, for important equipment such as central monitoring panels and disaster prevention panels, countermeasures should be implemented for each individual piece of equipment. For equipment that is sensitive to overvoltage, it is also possible to install a lightning transformer.
In addition, buildings have multiple grounding poles, and lightning surges enter when potential differences occur between these poles, so Class I SPDs are connected between each grounding to suppress potential differences.
In addition, the use of grounding resistance reduction material is very effective because it can smoothly neutralize lightning surges even when lightning strikes the building itself by lowering the grounding resistance value.

Installation example

Lightning protection products for buildings and structures