Can I feed 12VDC into a USB-6212 BNC?

[diarmaede]

I want to monitor a circuit that switches between 0 and 12VDC.  The voltage level will always be either 0 or 12VDC.

Can I feed this voltage into one of the AI channels of my USB-6212 BNC or will I fry something if I do.  The AI channels on the unit are only rated to +/-10V.  I don't care about getting an accurate voltage reading.  I only want to see if the signal is high or low.

Thanks!

[Kyle_A. · Accepted solution]

Hello,

Here are the overvoltage specs for this card:

Overvoltage protection (AI <0..31>, AI SENSE)
Device on ....................................±30 V for up to two AI pins
Device off ...................................±20 V for up to two AI pins

Input current during overvoltage condition ......................±20 mA max/AI pin

So you can input 12VDC into your board and not accurately measure, but you should be within specs to not damage the card.  If you can transform the voltage down or use external circuitry to decrease the input voltage within spec of the board, that would be best for ensuring correct operation and prolonging the life of the board to the greatest extent.