Connect photoelectric sensor to cDAQ and measure RPM

[maurlind]

Hi !

I have a photoelectric sensor that i want to use for RPM measurement on a rotating system. My problem is that I don't really know how to wire it to my NI modules. Is it possible to hook it up to my analog input (NI 9201)? 

According to the data sheet (see attachment), this snesor need a supply of 10...30v, and I have a analog output module NI 9263. Can I use that to generate 10 V to my sensor ?

Is it possible to use the DAQ assistant to aquire an analog input and then display the signal? After that I was thinking of converting the recorded volts to RPM.

In short, how do I connect this sensor to my cDAQ that has, analog input and output modules.

The sensor is called MHL15-P3336 from SICK.

Best Regards Maurlind

[Henrik_Volkers]

No, you can't use the analog voltage output, since it only provides a max current of 1mA per channel.

You need an external power supply to provide the ~30mA.  But you maybe you can use some mA of the cRIO power ??  (assuming you don't have a single slot device)

the output Q is a PNP, (connected to a AI), so you migth need a pull down resistor of 10k from Q/AI  to COM. 

COM also needs a connection to M

and  the +10 - +30V goes to L+ ( and  the neg to M)  

Depending on your RPM values..   have a look at the tone detection.vi  to find the puls frequency

[maurlind]

Hi!

I have a cDAQ 9178, with 4 slots in use. How can I use the mA from its power? 

Best regards Maurlind!

[Richard2950]

Your chassis has screw terminals for the power connections to the left of the modules. Run wires from the Vs and Com there to your sensor.

Rich

[Richard2950]

Also, you should connect your sensor Q output to a digital input, not an analog input. Use a pull-up (for NPN) or pull-down (for PNP) resistor.

[PBP]

You need external power supply for sensor. If you have 10V supply then your output will be 10-2.9=7.1V which can be connected to NI 9201(+/- 10V).  If you are planning to use different supply then you have to decrease your output voltage.

i.e If you are using 24V SMPS then use 24V to 5V converter (You can also build your own using opto coupler 4N33) and connect this 5V output to NI 9201. This arrangement is quite safe for NI9201