VHDCI (2 m) Analog Input The NI PXIe-7861 provides connections for 16 AI channels. Each channel has an AI+ pin, AI- pin, and AIGND pin to which you can connect both single-ended or differential voltage signals. Use the AISENSE pin to connect non-referenced single- ended signals.
NI PXIe-7861 Connecting Differential Voltage Signals You can connect grounded or floating differential signal sources to the NI PXIe-7861. Connect the positive voltage signal to the AI+ and the negative voltage signal to AI-. To connect grounded differential signals to the NI PXIe-7861, you must also connect the signal reference to AI GND.
Accessory NI PXIe-7861 To connect floating differential signals to the NI PXIe-7861, you must connect the negative and positive signals to AI GND through 1 MΩ resistors to keep the voltage within the common-mode voltage range. If the voltage source is outside the common-mode voltage range, the NI PXIe-7861 does not read data accurately.
When the system powers on, the DIO channels are set as input low with pull-down resistors. To set another power-on state, you can configure the NI PXIe-7861 to load a VI when the system powers on. The VI can then set the DIO lines to any power-on state.
Separate NI PXIe-7861 signal lines from high-current or high-voltage lines. ■ These lines can induce currents in or voltages on the NI PXIe-7861 signal lines if they run in parallel paths at a close distance. To reduce the magnetic coupling between lines, separate them by a reasonable distance if they run in parallel or run the lines at right angles to each other.
Caution Never connect the +5 V power terminals to analog or digital ground or any other voltage source on the NI PXIe-7861 or any other device. Doing so can damage the device and the computer. National Instruments is not liable for damage resulting from such a connection.
Need help?
Do you have a question about the PXIe-7861 and is the answer not in the manual?
Questions and answers