Campbell Scientific CS110 Electric Field Meter - Manual (Page 43)

CS110 Electric Field Meter
• Turbine studs
• Coal crushers
• Casting and Molding equipment
• Heat exchangers
10.3 Self-Check Features
The CS110 has been designed to provide reliable electric field measurements
and to simplify and minimize maintenance. Scheduled maintenance may not be
required, as the CS110 incorporates extensive self-checking, and provides
status information about each measurement. An example CS110 instruction
follows.
CS110(E_field,leakage_cur,status,_60Hz,Mult,Offset)
Returned E_field values of NAN (Not-A-Number) indicate a measurement
problem that can be determined from the associated status value.
The status parameter returned from each electric field measurement reports of
measurement problems along with instrument health. The CS110 status values
are described in Appendix A.
The leakage parameter returns the measured charge amplifier input leakage
current. A perfect unit is 0 nA. Actual units deviate from perfection such that
some have small (<< 1 nA) positive leakage current and some have small
negative leakage current. Occasional leakage current values exceeding
±4.2
nA may occur if insulators are wet. If leakage current values return to < ⎢1.0
nA ⎟ upon drying then no service is required. However, prolonged leakage
current values near to and exceeding ⎢4.2 nA⎟ are likely due to insulator
contamination requiring removal of the stator and cleaning.
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