Campbell CS110 - Protecting from Corrosion and Rust; Recalibration

8.5 Protecting from corrosion and rust
In corrosive environments, metal friction points (set screws, bolts, etc.) and electrical connections
to earth ground can be protected with the use of a rust inhibitor. Use the Loctite shipped with the
CS110 to lubricate all threaded screws to prevent corrosion and seizing.
8.6 Recalibration
Recalibration of instruments is commonly done in data-critical applications to combat
component drift with time. Component drift is a function of the environment experienced by the
instrument. High-humidity and/or high-temperature environments generally cause the most
drift.
The embedded CR1000M data logger module should experience a low-humidity environment,
which helps minimize data logger measurement drift. While measurement drift of the CR1000M
is likely negligible with regard to the ±5% of reading accuracy specification of electric field
measurements, the CR1000M drift may be a factor for the temperature measurement by means
of the external temperature and RH probe.
NOTE:
The CR1000 measurement accuracy is negligible in the overall CS110 accuracy, which is limited
by the charge amplifier circuit and mechanical dimensions of the shutter, stator, and sense
electrode. Therefore, the CS110 accuracy specification remains valid after replacing or
recalibrating the CR1000.
Each CS110 is factory calibrated in the parallel plate calibrator to determine individual instrument
gain (see Factory calibration of the CS110 (p. 20)). The CS110 electric field measurement
instrument gain is a function of electrode dimensions, along with the 1% feedback capacitor used
in the charge amplifier.
A parallel-plate calibration is recommended whenever any electrodes are bent, removed, or
replaced, with the exception of the removal and replacement of the same stator during the
process of insulator cleaning. For applications requiring long-term electric field measurement
accuracy better than ± 10%, a parallel plate factory calibration is recommended every 3 years.
The expected lifetime of the CS110 is 5 to 10 years, again depending upon the operational
environment. Instruments operated in coastal environments will likely suffer from external finish
degradation and/or operational failure sooner than instruments operated in dry inland
environments.
CS110 Electric Field Meter 32