Manual

Section 7. Grounding

7.1.1 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

available, Campbell Scientific has for many years 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 CR200(X) and associated

sensors and power supplies.

In addition to protections discussed in ESD Protection (p. 55), 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

lightning strike. FIGURE. Lightning Protection Scheme (p. 57) shows a simple

lightning protection scheme utilizing a lightning rod, metal mast, heavy gage

ground wire, and ground rod to direct damaging current away from the

CR200(X).