System level grounding serves two main purposes in Vaisala systems:
- Electrical safety grounding (also known as earthing) in mains powered systems reduces touch voltages and ensures proper operation of the safety components inside a system in fault conditions.
- Lightning protection grounding enables the lightning protection systems and transient protection devices to operate as intended to protect the system and reduce the risk of dangerous step voltages on ground near the system.
The same grounding system may serve both needs although the requirements for optimal performance can be quite different.
| The recommended practices in this manual do not cover all the requirements of every standard and specification available. |
When designing a lightning protection system and the grounding of a site, take into account the structure to be protected and the needed protection level, as well as technical, geographic, and economic factors.
The general principle in grounding Vaisala weather station systems and masts is to install a lightning protection system, including an air terminal, down conductor, and a ground electrode, and ground the mast and the electronics enclosure with separate wires. See System and Equipment.