About PXI-8423.

[lqyun]

In the datasheet of PXI-842x, it was been mentioned that the transfer rates of RS-485 is 460kbps. What I want to ask is that this performance character is defined by which cable length? Does it mean that by using 1200ft cable the 485 module can meet 460kbps?
Or the maximum transfer rate is 460kbps, no matter how long the cable is?

[Chris_Rake]

The max rate is indeed 460.8k, as determined by the baud clock of the UART. Cable capacitance plays the largest role in limiting data rates, and different cables will have different capacitance. However, you should be able to go up to 500m (maybe even 1000m) at 460.8k with the PXI-842x RS-485 interface cards and typical RS-485 cables.