CR1000 Manual - Campbell Scientific

Section 7. Installation
Figure 31: Schematic of grounds
7.5.1.1 Lightning Protection
The most common and destructive ESDs are primary and secondary lightning
strikes. Primary lightning strikes hit instrumentation directly. Secondary strikes
induce voltage in power lines or wires connected to instrumentation. While
elaborate, expensive, and nearly infallible lightning protection systems are on the
market, Campbell Scientific, for many years, has employed a simple and
inexpensive design that protects most systems in most circumstances. It is,
however, not infallible.
Note Lightning strikes may damage or destroy the CR1000 and associated
sensors and power supplies.
In addition to protections discussed in ESD Protection (p. 86), use of a simple
lightning rod and low-resistance path to earth ground is adequate protection in
many installations. A lightning rod serves two purposes. Primarily, it serves as a
preferred strike point. Secondarily, it dissipates charge, reducing the chance of a
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