How to connect a pressure transmitter

[Boozz]

Hi,

I (actually my boss, but who cares) bought a NI-DAQ-card type: PCI-MIO-16E-4
from NI. I want to use it in combination with LabView. What's the best
connection to get some good data from this transmitter.

By the way, I'm a mechanical Engineer, so please be carefull with me when
you're talking electronics...

Transmitter is:
Endress+Hauser
it needs a 11..30 VDC power supply,
2-wire type, 4..20mA output.

Do I have to use an external power supply? How do I best connect these
things?

To be more precise: I'd like to connect 3 of them...


Thanks,

Ronald

[Kevin_work]

Boozz wrote:

> Transmitter is:
> Endress+Hauser
> it needs a 11..30 VDC power supply,
> 2-wire type, 4..20mA output.
>
> Do I have to use an external power supply? How do I best connect these
> things?
>

You will need an external power supply. Most likely a single power supply will
run all three.

You dont specify the output voltage though it is probably ok.
If it is greater than + / - 10V then you will need a voltage divider.

I am not sure about the MIO board but it probably does not have current sensors

(someone correct me if I am wrong). If that is the case then you will need some
way
to convert the current to a voltage. There are several methods the simplest
being
placing a resistor inline and measuring the voltage drop across it.

I would suggest looking to th
e manufacturer for information or contacting
your inhouse EE's (if you have them).

Hope this helps more than hurts.
Kevin Kent

[Steve Gomez-Leon]

First you need to buy a power supply for the pressure transducer, probably
a 24 Vdc supply. The nidaq card can only measure voltage from -10 to +10.
So you need to convert the current output on the transducer to a voltage.
Connect a resistor from one lead to another and use the nidaq card to
read the voltage across the resistor. Use a resistor that maximizes your
resolution. Since you have a 4-20mA transducer, a 500 ohm resistor
will read from 2-10V, and a 250 ohm resistor will read from 1-5V.
The larger the range the better.

By the way, if you haven't bought it yet, you will need a breakout
box and cable connector for the card. I use the BNC 2090 breakout
box and two cables (183569B-01 and 182419B-01) to connect to my
PCI-MIO-16E-4 card.

Boozz wrote:

> Hi,

>
> I (actually my boss, but who cares) bought a NI-DAQ-card type: PCI-MIO-16E-4
> from NI. I want to use it in combination with LabView. What's the best
> connection to get some good data from this transmitter.
>
> By the way, I'm a mechanical Engineer, so please be carefull with me when
> you're talking electronics...
>
> Transmitter is:
> Endress+Hauser
> it needs a 11..30 VDC power supply,
> 2-wire type, 4..20mA output.
>
> Do I have to use an external power supply? How do I best connect these
> things?
>
> To be more precise: I'd like to connect 3 of them...
>
> Thanks,
>
> Ronald