Campbell CRVW3, Инструкция по эксплуатации

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CRVW3 3-Channel Vibrating-Wire Datalogger
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(chassis) grounded. All components of the system (dataloggers, sensors,
external power supplies, mounts, housings, etc.) should be referenced to one
common earth (chassis) ground.
In the field, at a minimum, a proper earth ground will consist of a five-foot
copper-sheathed grounding rod driven into the earth and connected to the large
brass ground lug with a low gage wire (8-12 AWG). In low-conductive
substrates, such as sand, very dry soil, ice, or rock, a single ground rod will
probably not provide an adequate earth ground. For these situations, search for
published literature on lightning protection or contact a qualified lightning-
protection consultant.
For information on the ESD testing of the CRVW3, see Appendix
F , ESD Testing
(p. F-1)
.
8.2.6.1.1 Lightning Protection
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. The
system employs a lightning rod, metal mast, heavy-gage ground wire, and
ground rod to direct damaging current away from the datalogger. This system,
however, is not infallible. FIGURE 8-16 is a drawing of a typical application of
this simple design.
Lightning strikes may damage or destroy the CRVW3 and
associated sensors and power supplies.
NOTE
NOTE