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Recommendation for NI card to use as Power Supply of 5VDC, 1 to 20mA current range?

I have NI cRIO-9024 Real time controller connected on a chassis. I need a card for proving DC supply(which can be controlled through Labview) to a sensor. I am looking for a suitable NI card for inserting on my chassis connector  to do so. Can someone recommend me which one should i buy?

 

The main requirement is to control the current using Labview. The budget is not a problem. The solution is the main thing.

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You're using Ben's avatar, although it is a low resolution version without the glinty eye.


aputman
LabVIEW 2017
LabVIEW Programming
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@ZohaibRamzane wrote:

I have NI cRIO-9024 Real time controller connected on a chassis. I need a card for proving DC supply(which can be controlled through Labview) to a sensor. I am looking for a suitable NI card for inserting on my chassis connector  to do so. Can someone recommend me which one should i buy?


Probably not (although maybe someone will, and I'm wrong).


@ZohaibRamzane wrote:

I have NI cRIO-9024 Real time controller connected on a chassis.

The main requirement is to control the current using Labview. The budget is not a problem. The solution is the main thing.


On the other hand, you can definitely control discrete power supplies with LabVIEW (and the cRIO-9024). The 9024 conveniently appears to have a DE-9 RS232 connector, which would allow you use something like VISA Read/Write commands to communicate with a RS232-capable power supply.

I'm using a pair of these (PW24-1.5AQ) with a cRIO-9045, but they're by no means the only option (and I haven't compared them, either in performance or price, to other options - so I'm making no specific recommendation). In this case, the RS232 support requires a separate card to be installed in the back (it's an optional module for the power supply).


GCentral
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Thank you for your help.  

Can you suggest some article to control power supply through RS232 port!!

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There is a C series output current module NI 9265. Can i use this one for dc supply of 5V, with 1-20mA current range(controlled via labview on chassis cRIO 9024.

 

Kindly answer me on this too if possible. 

 

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@ZohaibRamzane wrote:

There is a C series output current module NI 9265. Can i use this one for dc supply of 5V, with 1-20mA current range(controlled via labview on chassis cRIO 9024.

 

Kindly answer me on this too if possible. 

 


If you read the datasheet (literally the first paragraph) you'll see the 9265 requires an external power supply with 9-36V.

The module would allow you to control the output current, from 0 to 20mA, but not the resulting voltage.

 

Presumably what you want is a 5V output, which is capable of remaining at 5V even when sourcing/sinking 20mA. That's not what the 9265 is for at all.

You need a power supply, separate from the cRIO system (although as I already suggested, you could pick one which can be programmatically controlled by a cRIO or some C-series modules).

 

If you only need to turn it on and off, you could use a power transistor and a fixed power supply, then use a digital output from a C-series module to toggle the transistor.

 

Regarding the previous request for a document/article about controlling a power supply through RS232, no. If you choose a power supply, then try programming it, you could ask a new question about any difficulties you have.

As it stands, the question is far too open-ended to try and answer.

For examples of using VISA to control external devices, look at the VISA examples. It's the same on cRIO as it is on desktop (which is nice, because you can test more quickly with a USB to RS232 adaptor on desktop than via the built-in port on a cRIO chassis).


GCentral
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"You need a power supply, separate from the cRIO system (although as I already suggested, you could pick one which can be programmatically controlled by a cRIO or some C-series modules)."

I understood what you said that it is not possible to mantain 5V if i draw upto 20mA current from NI 9265 .

 

Kindly is there any related info on this; which power supply(brand) and how i can program it using cRIO?

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Probably any vendor that produces power supplies with external control available will have a manual describing the communication methods possible.

Some of them may offer included LabVIEW drivers. I don't know of any, but I expect there are some.

 

I'd suggest finding your favourite online electronics store, or electronics supplier, etc, and looking at what they have available. LabVIEW is pretty capable - anything that has something you can connect to will probably be controllable with enough effort. The more the manufacturer provides, the less you'll have to do (unless they did a horrible job and you need to write it from scratch anyway... sometimes it happens!)

 

The example I gave previously responds to a collection of string commands sent via VISA Read/Write. I wrote the driver myself and tested it on my laptop before moving it onto the cRIO system we have (9045).

 

As a side note, I reread the opening post and see you specifically want to control current. Is that true? Can you recap your application, and perhaps some information about the sensor in question, to make sure I (or others) don't misguide you? Previously I'd thought you wanted a fixed voltage with a current that was capable of supplying up to 20mA.

If you want a fixed current and you intend to measure voltage drop over a resistor (e.g. an RTD or similar) then you could still do that with the power supply I suggested, but the 9265 becomes a more worthwhile consideration as a method of control rather than changing the values output by the power supply directly.


GCentral
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I am doing experiment in which i have to measure the temperature value of pt-100(one experiment) and thermocouple (2nd experiment). For input to pt-100, i need controlable current range to see effect on temperature as we increase current value(0 to 20mA) with voltage fixed at 5VDC.

Same experiment with thermocouple repeats.

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How will you vary the current and keep a fixed voltage across a ~100 Ohm resistor?

For a thermocouple, you don't feed a current - you're instead measuring a very small voltage (usually with an amplifier to make it less "very small").


GCentral
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