Lightning-absorbing design - Lightning countermeasure consulting


Lightning-absorbing design

We design lightning countermeasures for the entire facility.

Lightning countermeasures vary depending on various conditions such as the location of the building and electrical wiring. We listen to the customer’s needs, prioritize what they want to protect the most from lightning, and come up with countermeasure proposals.
Based on our long years of know-how, we design countermeasures with high investment effectiveness, taking cost effectiveness and safety into consideration, and propose them to our customers.

OTOWA designs not only SPD, but also lightning protection for buildings with lightning rods and other equipment in a consistent manner.

OTOWA designs not only SPD and other electrical equipment, but also lightning protection for buildings using lightning rods and other devices. OTOWA designs all external lightning protection measures such as lightning rods (lightning receiving parts), trailing conductors, and grounding poles.

Comprehensive lightning protection measures are made up of two pillars.
  • Protection of buildings, etc.: Measures against direct lightning strikes (lightning protection: physical damage to buildings, etc. and danger to human life JIS Z 9290-3)
  • Protection of electrical equipment: Measures against lightning surges (Lightning protection: Electrical and electronic systems in buildings JIS Z 9290-4)

Design in accordance with the latest JIS

Design and installation of the most suitable grounding electrode system according to geological and other conditions.”

Points for lightning surge protection (lightning protection of electrical equipment)

The reduction of lightning surge is implemented using not only SPD and lightning arrestors, but also three other methods. In particular, measures for shielding (shield) are judged not only from drawings, but also by actually seeing the site, and the best design is made.

Reduce lightning surges to below the insulation level of the equipment
  • SPD and surge arrestor
Eliminate the path for lightning surges to enter (insulation)
  • Power line: lightning transformer
  • Signal line: Fiber optic cable (However, if the tension member is made of metal, care must be taken in its treatment.

We have designs that are possible only as a specialized lightning protection manufacturer.

We use a variety of know-how to create optimal designs, such as taking into account grounding resistance and wiring length to reduce the impact of lightning surges; we conduct lightning immunity designs based on JIS, and consider the condition of the equipment from various perspectives, such as checking the lightning protection level and lightning protection zone. In addition to designing based on JIS, we also make optimal designs for facilities based on various information we learn from field surveys, such as the soil conditions (grounding resistance) and wiring conditions of the facility.

It is important to install the appropriate SPD and surge arrester at the appropriate location.

There are various points to consider when selecting an SPD, and because OTOWA is a specialized lightning protection manufacturer, we can select the SPD and surge arrester that best suits the equipment. For SPD for power supply, it is necessary to select the most suitable SPD after confirming the “circuit voltage,” “type of system,” “DC/AC,” and “voltage,” “frequency,” and “number of signal lines” for communication and signal lines. We also handle high-voltage surge arresters, such as 3.3kV and 6.6kV distribution surge arresters and cubicle surge arresters, so we can offer a comprehensive range of lightning protection solutions from high-voltage to low-voltage.

Lightning arresters for 6.6kV power distribution.