Using Chopping to Remove Offset Voltages

Chopping is a feature that can be used to remove offset voltages and other low frequency errors. The signal is measured twice, once normally and once with the inputs inverted. These measurements are then averaged by the device to create each sample.

The NI 4309 supports chopping but disables it by default. Chopping can be enabled with the AI.Chop.Enable attribute/property, or when configuring a voltage input task in the DAQ Assistant by selecting the Enable Chopping option. Refer to the NI 4309 User Manual for wiring instructions.