Lightning Rod and Surge Arrester
Both have different functions. It is better to install both.
- The lightning rod solves the problem of direct strike.
- Surge arrester overcome indirect struck problem.
Lightning rod function for lightning strikes not about buildings or devices. The current from lightning is disposed to large cable land. If the current passes through the building, then the building can be burned/damaged.
The current of lightning can generate magnetic field, which can get into power cord or other cables nearby. This current induction can be entered into an electronic device. Surge arrester functions throw more current/voltage on the wires to the ground, so the current does not go into the device.