USB-3106 0-20mA connections..

[keef44]

I am trying to use the current outputs on a USB-3106 module.

The device i am connecting it to has the following connections Signal input, GND and 12VDC. I have tried connecting AGND to GND and IOUT to Signal Input - does not work.

The manual is a little confusing....

Any ideas??

Edited November 13, 2023 by keef44
typo

[Fausto]

Hello @keef44.

Please provide a datasheet and/or user's guide for your external device.

Regards,

Fausto

[keef44]

Its own device.... 

See the image attached which shows an example input circuit.

The PCB is designed to work with 2 wire 4-20mA sensors (so the sensor has Signal (4-20mA), GND and 12VDC supply voltage.

[Fausto]

Hello @keef44.

Are you using the USB-3106 in place of 4-20mA sensors only to test your PCB design?

Is the +12VSAFE used by your 4-20mA sensors and/or your PCB design?

 

Is your 12 VDC supply voltage isolated from ground (floating) or grounded?

With that, then you can determine whether to use the left-side or right-side of figure 6 in the USB-3106 User's Guide.

 

 

 

[keef44]

I want to use the USB-3106 to simulate the sensors - for software testing.

+12VSAFE is normally used to provide power to the remote sensors.

The +12VSAFE is grounded.

 

[keef44]

I am still unable to get this to work....

I have also tried using a 0-10VDC output with a 500R resistor in series to my devices input - does not work either, only reads up to 8mA?

[keef44]

Just tried something - if i wire it up like this...

It works with 1 x channel connected - but with 2 x channels, the signal seen is at 50% of what it should be on each input.

Edited November 22, 2023 by keef44