Voltage And Current Excitation - Campbell GRANITE VOLT Series Product Manual

Terminals
VOLT 108:
VOLT 116:
1,2
Accuracy
0 to 40 °C:
–40 to 70 °C:
–55 to 85 °C:
1
Assumes input reversal for differential measurements and excitation reversal for excitation voltage <1000 mV and
excitation current <1 mA, not including bridge resistor errors and sensor and measurement noise.
2
See GRANITE 6 Data logger Manual for help estimating measurement accuracy for ratiometric measurements. For
Resistance()
instruction, the excitation current is internally measured across an internal resistor (200 Ω, ±0.005%
@ 25 °C, 2 ppm/°C TCR) with sensor resistance determined as Vs/Ix, where Ix is the measured excitation current and
Vs is the returned sensor signal.

8.3 Voltage and current excitation

Two terminals on the VOLT 108 and four terminals on the VOLT 116 can be configured for voltage
or current excitation using a 12-bit D-to-A converter. When used for ratiometric-resistance
measurement, excitation is active only during measurement.
Terminals
VOLT 108:
VOLT 116:
Voltage excitation
Range:
1
Accuracy
0 to 40 °C:
–40 to 70 °C:
–55 to 85 °C:
Resolution:
SE terminals 1 – 16
DIFF terminals 1H/1L – 8H/8L
Excitation terminals X1 – X2
SE terminals 1 – 32
DIFF terminals 1H/1L – 16H/16L
Excitation terminals X1 – X4
±(0.02% of voltage measurement + offset)
±(0.025% of voltage measurement + offset)
±(0.03% of voltage measurement + offset)
X1 – X2
X1 – X4
±5000 mV
±(0.05% of setting + 2.5 mV)
±(0.08% of setting + 2.5 mV)
±(0.1% of setting + 2.5 mV)
1.25 mV
VOLT 100 series 17