How can I protect a DAQ-Input against over-voltage ?

[DaRo]

I have a NI 4472 DAQ together with NI 2501 multiplexer. How can I protect the input ports against over-voltage ?

[dcourtri]

You could use some zener diodes or varistors. The 2501 and the 4471 only provide a voltage range of 10 Volts. If voltage is of concern the 445x provide a voltage range of 42 volts and the 2503 has a voltage range of 30 volts. This would allow for more lenient voltage variations.