VM 140 and 4-20 mA

Modules PC Related Projects
1

Good morning Vellemann Moderators and Forum Friends,
i have still a problem connecting 4-20 ma Sensors to the VM 140 Modul.
I asked already some weeks ago for that. But :
I want neigther destroy the card nor the sensor transmitter.
i want to make sure, to connect it right
To explain the prob i would like to add a jpeg file. Is that possible ?

Best rgds
Rudolf

2

There is no risk to destroy the current loop sensor.
The only thing you need to do is to put a resistor parallel with the input of the VM140 analog input.
For a 5V analog input, you need to put a 5/0.020 = 250 ohm resistor (= four 1K resistors in parallel).
For a 10V analog input, you need to put 10/0.020 = 500 ohm resistor (= two 1K resistors in parallel).

3

Tanks for your answer.
Sorry for bothering.

I am very unexpired in electronics, thats why i ask again.

It means for fools like me:
i put a resistor 250 Ohm , one side on the VM 140 analog input,
the other side on GND.
I even connect the sensor Output to the analog input.
The flow is going thrue the resistor and the voltage changes in proportinal.

Is that right ?

I actually added 10 actors and 7 sensors to this perfect card,
I could easy do a programm with VB.

The only prob. is this mA sensor
Please help me.
Best Regards
Rudolf

4

This is correct.

5

Hey your still working.
Thanks a lot, i will try.