Lightning strike point/ Conduction/ Basic principles of lightning protection

SPD is installed between lightning strike point and protected equipment.

Basic principles of lightning protection:

1. SPD should be installed close to the protected equipment. The closer the better.

2. Equipotential connection.

3. All external circuits need lightning protection

Selection of guide line:

To achieve the best protection effect, the guide line which connects to SPD should be short. The shorter the better

Based on the standards of electric power department, the CSA of guide line should be the same with original circuit, or larger.

Low-voltage SPD

Influenced by connection, the shorter the better. As far as possible to avoid bending.

Installation of SPD’s three-level power in weak electricity engine room

Level B cooperate with Level C to reduce lightning to harmless.

SPD are installed in different power supply system.

Comparison diagram of lightning current waveform.