MoTeC SDL - Manual (Page 12)

10 Overview
These inputs can also be used to measure two wire variable resistance
sensors if an external pullup resistor is connected from the input to the 5V
sensor supply. Additionally, on/off switch signals may be connected, which
may also require an external pullup resistor.
Measurement Methods
These inputs can be configured to use several measurement methods to suit
the various types of sensors:
• Absolute Voltage: The sensor voltage is independent of the sensor supply
voltage
• Ratiometric Voltage: The sensor voltage is proportional to the 5V sensor
supply voltage
• Variable Resistance: The sensor resistance can be entered directly.
• On/Off : The voltage for on and off can be defined
Input Voltage Range
The measurable input voltage range is 0 to 5.5V on inputs AV1 to 4 and is 0
to 15 Volts on all other AV inputs.
Specifications
For full specifications see Appendix D: Input Characteristics.
Analog Temp Inputs
The 4 Analog Temp inputs are identical to the Analog Voltage inputs, except
that they contain a 1000 ohm resistor which is connected internally from the
input pin to the 5V sensor supply. This allows the Analog Temp inputs to be
used with two wire variable resistance sensors such as:
• Two wire thermistor temperature sensors
• Two wire variable resistance pressure sensors
Some voltage output sensors can also be used if they can drive the 1000 ohm
resistor without causing an error in their reading (eg MoTeC Thermocouple
Amplifier). Additionally, on/off switch signals may be connected.
Measurement Methods
These inputs use the same measurement methods as the Analog Voltage
Inputs.