Auxiliary channels can be used to connect various high level sensors for measuring for example movement, respiration, pressure, flow, galvanic skin response, temperature, etc.
Each auxiliary input has a 5-pin connector. Signals on this connector are +5V output, -5V output, GND, +signal input and -signal input. The +5V/-5V/GND pins can be used to power an active sensor. The + and - inputs are connected to an instrumentation amplifier with a gain of 1. An unconnected input will automatically be switched of (i.e. will show a zero signal). The output of the amplifier goes to the ADCs without any filtering.