Digital input via STG DSUB-9 connector

Hello,

I have and IOLITE-6xSTG module and I would like to measure the activation of a small relay. The relay is activated via another device wich gives a 3.3V digital signal that opens the mentioned relay. What I would like to have is the information of the relay activation both recorderd and displayed in measure mode. I know there are specific modules for this application, but couldn't I just bring the aforementioned relay signal to one of the pins of my DSUB-9 connector and this way record the activation? If so, how can I set up the channel?

Thanks in advance,

Francesco Miccoli

Dear Francesco,

I don't know the application exactly however based on your description I would suggest setting simple voltage measurement. On the picture below you can see the settings in the Ch. setup as well as the corresponding wire connection to the appropriate pins of the DSUB9 connector. The "Sensor" side would be treated as relay. More about connector you can find in the IOLITE manual: https://download.dewesoft.com/download-file/dewesoft-iolite-manual-enpdf

Since analog input devices are high resistance / impedance, you will need a resistor or similar tied to ground otherwise when the relay is closed the voltage won’t drop off quickly enough to be useful.