voltage pulse outputted by inductive sensor lowered when plugged to NI 9401 for counters

[kodj]

Hi,

We have tested the voltage output the sensor XS618B1PAM12 with module 9401. When unplugged from 9401 the voltage output is approximately 5V and it is indicated by LED light on inductive sensor (see Pic).

When plugged to 9401 module the voltage output is around 0.46V and the indicating light on LED sensor is so weak. (see pic below). How can we resolve this issue, we actually need the inductive sensor to output the 5V voltage pulses?

Thanks.

Kodjo

[Buechsenschuetz]

I have no experience with the 9401 module. But since this is a bidirectional module, are you sure that the I/O lines your sensor is connected with are configured as inputs? As long as they are configured as outputs, they will more or less (unpredictable) "shorten" the output signal of your sensor. 

[AnalogKid2DigitalMan]

Specs here:

http://docs-europe.electrocomponents.com/webdocs/0a9c/0900766b80a9c49f.pdf

Looks like that prox needs 12-48VDC and has a PNP output, what voltage are you supplying it?

It may not operate properly when connected to a load when supplied only 5V.

Since the 9401 is TTL level (5V) you will need a resistive voltage divider at the output of the prox to reduce the level to 5V when ON.

-AK2DM

[kodj]

Yes they are configured as inputs. I don't have a lot of knowledge about hardware. I am still stuck with the issue

[kodj]

Sorry I am working with 24V voltage supply. I have tested the cRIO 9073 with 9401 module with 24V voltage when I am using a switch to generate counter and it works fine. I have also tested the proximity sensor standalone and works perfectly fine generating 24 V pulses. However when I pluge a wire from output proximity sensor to terminal connected to NI 9401 the voltage pulse is alternating around 0.46V (weak LED light on proximity sensor) . You can see the screenshot I have previously attached earlier.