Connecting a light barrier (NPN or PNP) to an Arduino

Other Hardware Sensors
1

Hello,
I need to connect a light barrier (NPN or PNP) to an Arduino.
I am powering the barrier with 24V.
I need to be able to send the information that an object has been detected to my Arduino.
How can I do this safely?

Some information obtained from the manufacturer:

Barriere2
Barriere21131×385 58.5 KB

Barriere1
Barriere1995×655 42.1 KB

Merci d'avance

2

The safest option is to use an optocoupler.

2 Likes
3

Thanks for your response.
Seems to be a good option.
Need to test.

Thanks to you to take the time to write your response

4

What is the maximum / minimum current for the NPN or PNP output?

5

I'd first try wiring a led, with a 4.7k series resistor between, 24v and NPN. It is not clear from the document if the led will be on or off during a detection but that would be the first thing you would discover with this experiment.
The optocoupler is a good idea so you don't have to share either of the 24v supply power rails with the Arduino.

6

Is your npn output an open collector output?
In that case you can put the load resistor on the 5V rail (instead of the 12 V rail and read the signal from the grey cable).