So you may have already installed lightning arrestor on your house , factory oor in your office. But how do we take note that really the LA took the lightning and grounded it?
There comes Lightning arrestors counter.
Lightning strike counter is attached to the cu strip which comes to the ground from LA.

When lighting is flown though the CU bar it will start counting. Here it is used electro mechanical counting system . If you wanna rest the counter you will have to use separate terminals for resetting the count.
There are two types resstable and no resettable Lightning strike counters. Make sure you purchase according to your requirement.