Campbell Scientific CS110 Electric Field Meter - Manual (Page 34)

CS110 Electric Field Meter
Single-ended voltage measurements are referenced to ground, rather than the
low side of a differential input. The VoltSE single-ended measurement
instruction is quite similar to the VoltDiff instruction and is given as follows:
VoltSe (Dest,Reps,Range,SEChan,MeasOff,Settling Time,Integ,Mult,Offset)
An internal ground reference is utilized in single-ended measurements. Single-
ended offset errors are reduced in single-ended measurements by measuring the
voltage on the internal ground reference. The MeasOff parameter in the
VoltSe instruction determines if this internal ground reference is measured at
the beginning of every VoltSe instruction (MeasOff = True) or whether a
single-ended offset voltage measure is performed as part of an on-going
instrument self-calibration routine occurring in background (MeasOff = False).
Another general purpose voltage measurement instruction is the BrHalf
instruction, which provides voltage excitation for a simple resistive divider
(half of a 4-element Wheatstone bridge), and then measures the resulting
voltage.
A BrHalf instruction follows:
BrHalf (Dest,Reps,Range,SEChan,ExChan,MeasPEx,ExmV,RevEx,Settling
Time,Integ,Mult,Offset)
Most parameters of the BrHalf instruction are common to the VoltDiff and
VoltSE instructions, and so only the differences will be discussed. The
ExChan parameter determines which one of the three CR1000 voltage
excitation outputs are used to excite the half-bridge. MeasPEx determines how
many successive channels are excited by the same excitation channel in
successive Reps. ExmV determines the excitation voltage which can range
from –2500 mV to +2500 mV. RevEx is a true/false parameter and if true then
the polarity of the excitation is reversed during the measurement and a second
measurement taken. Like input reversal on differential measurements,
excitation reversal is an error canceling technique for reducing low-frequency
measurement errors such as offset voltages.
The Battery instruction is used to measure the input voltage of the power
supply to the CS110 and follows:
Battery (Dest)
The PanelTemp instruction is used to measure the temperature of a thermistor
located within the CS110 case and follows:
PanelTemp (Dest,Integ)
The PulseCount instruction is used to count the pulses generated from sensors,
such as an anemometer or switch closures from a tipping bucket rain gauge,
and has the following parameters.
PulseCount(Dest,Reps,PChan,PConfig,POption,Mult,Offset)
PChan is the number pulse channel (1 or 2) used for the measurement.
PConfig is a code (0-2) for three different types of pulse-count inputs; High-
frequency = 0, low-level AC = 1, and switch closure = 2. POption is a code to
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