Sutron 8310 - Analog Input Sensor Connections

Sutron Corporation 8310 & 7310 Users Manual 8800-1125Rev. 2.7 (BETA) 4/16/2014 pg. 159
Input/Output Expansion
Additional analog and digital inputs and
outputs can be added via external I/O
expansion modules.
Module Types
Analog, 10 channels, 16 bit
Digital, 8 channels, input or output
In addition to the external input capability, the 8310 can monitor and log
several of its own internal functions including:
excitation voltage
Analog Ground voltage
+5v A/D reference voltage
Main Battery Voltage
Analog Sensors
Analog sensors are sensors with a voltage output. This voltage can be the result from:
a reference voltage passing through a resistive device
a powered sensor that has a voltage or current output
a self-powered sensor a voltage or current output
Sutron provides 4 different input types for making measurement of analog sensors: voltage,
bridge, resistance and 4-20ma. The following table shows the input type best suited for
common analog sensors
Sensor
Voltage
Bridge
Resistance
4-20ma
Potentiometer
X
X
Potentiometer,
high accuracy
X
Thermistor
X
Thermocouple
X
Load Cell
X
Pressure
Transducer
X
Pyranometer
X
RTD
X
0-<+5VDC
X
+/-2.5VDC
X
4-20ma
X
Examples of resistive sensors are potentiometers that are found in many wind direction, gate
opening, and position sensors. Other resistive sensors compatible with the 8310 are thermistors
and thermilinear sensors (for temperature) and pressure sensors. Sutron uses a +2.5V reference
voltage for these resistive devices and reads the voltage on a 0-5 volt scale with a 16 bit
converter. The sensor should have a resistance of at least 500 ohms and have enough change in