I need some help trying to pull reasonable data from a reed switch. The setup that makes common sense to me is the one I am currently using. I have a resistor between the switch and the NI PS-15 power supply in order to step the current down below 20mA. The normally open reed switch is a two wire instrument where the impulse is measured across the two wires. My engineering common sense dictates that I should use a NI 9203 C-series card to hook up to my cRIO-9073. This is because the 9203 is a current input module. As the reed switch is normally open, the current should register as 0. Then when the switch is closed, the current flows to the card returning a readable value. The switch has an LED embedded within the sensor itself so I can physically tell when the switch is closed. However, the 9203 card is not returning any value greater than around 0.1 microamps. The current across the resistor I measured at around 15 milliamps. I am terribly confused and if anyone would be able to offer help or guidance that would be phenomenal. Thank you for your time.
