Interfacing a 2200 power supply with LabVIEW 8.2

2200-20-5, 2200-30-5, 2200-32-3, 2200-60-2, 2200-72-1, 2220-30-1, 2230-30-1
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joerichards87
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Interfacing a 2200 power supply with LabVIEW 8.2

Post by joerichards87 » June 19th, 2014, 10:03 am

I have a 2200 single channel power supply that I am trying to control remotely using LabVIEW 8.2. I only need basic functionality (i.e. voltage/current outputs and setting voltage limits). The front panel of the power supply indicates that it is in remote mode. When I try to manipulate any of the settings from labVIEW nothing happens. I believe I have the right drivers installed. The code I'm using is attached.

I'm pretty new to LabVIEW, so any dumbed down advice of things to try would be appreciated.

Thanks,
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Example_VI.vi
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Dale C
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Re: Interfacing a 2200 power supply with LabVIEW 8.2

Post by Dale C » June 20th, 2014, 7:58 am

Try this. Maybe it will help.
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2230setvoltreadcurrent.vi
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joerichards87
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Re: Interfacing a 2200 power supply with LabVIEW 8.2

Post by joerichards87 » June 20th, 2014, 2:08 pm

Thanks,

That works great for constant voltage mode. How do I switch to constant current mode?

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Re: Interfacing a 2200 power supply with LabVIEW 8.2

Post by Dale C » June 23rd, 2014, 8:15 am

Hello Joe,
The Model 2200 is a power supply. It is a voltage source with a current limit.
The constant current mode is load dependent.
This means if you have say, 10V and a current limit of 1A. Then the load is 5 ohms.
The current limit is reached.
Now the unit becomes a constant current source and a lower voltage.
There no constant current mode command.

joerichards87
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Re: Interfacing a 2200 power supply with LabVIEW 8.2

Post by joerichards87 » June 26th, 2014, 1:55 pm

Ok that makes sense.

So I've incorporated this block diagram into a while loop in another block diagram that monitors/controls a few relays dependent on variables in my circuit. After the program runs for a few minutes LabVIEW freezes then crashes giving me an error message about memory. Is there some way that I can dump or reallocate memory after each loop?

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Re: Interfacing a 2200 power supply with LabVIEW 8.2

Post by Andrea C » June 27th, 2014, 4:52 am

Hi Joe,
You should not have to manage the memory in that manner.
How are you controlling the relays? Do you have some sort of digital IO hardware with it's own LV driver?

To determine where the problem is, you may need to test with a small program that uses just your relay control code and then separately test with code that just uses the VISA read and write VIs that interact with the power supply.

Andrea

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Re: Interfacing a 2200 power supply with LabVIEW 8.2

Post by Kenneth P » June 27th, 2014, 9:56 am

Can you provide more detail regarding the memory error? If the 2200 supply reports any error message relating to the memory, it would be error message -225 (out of memory). This error message, however, should not freeze and subsequently crash LabVIEW operation. The VISA default timeout would be honored and move to the next step. Does the power supply also freeze? Is it necessary to cycle power to regain control of the power supply?
You might want to introduce some error trapping within the test loop to break out of the loop or add a STOP to prevent LabVIEW from crashing should an error occur. I suggest reviewing the Status and Event system and incorporate SRQ coding. Sorry that this may be a bit more advanced but it is a good method to isolate the condition

joerichards87
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Re: Interfacing a 2200 power supply with LabVIEW 8.2

Post by joerichards87 » June 27th, 2014, 2:46 pm

I reduced the byte count on the VISA read function and that seems to have fixed the crashing problem, though it doesn't make sense as to why? But it is working for now so thanks for the help.

el.moreno
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Re: Interfacing a 2200 power supply with LabVIEW 8.2

Post by el.moreno » October 4th, 2014, 12:23 pm

Hello,

I am looking to purchase one of these power supplies strictly because I can program it with LabVIEW.
One of the things I wanted to use it for was to provide power to this thermoelectric cooler.
http://www.hebeiltd.com.cn/peltier.data ... -12706.pdf
It has a load of about 2 ohms.
To use it properly, I would need to keep current constant at about 1.5 A according to the pdf.
I was wondering it would be possible to do that with this power supply while changing the voltage?
Is this the constant current functionality that comes with it?

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Re: Interfacing a 2200 power supply with LabVIEW 8.2

Post by Dale C » October 6th, 2014, 8:45 am

The constant current mode of the 2200 series is basically the current limit mode.
When the unit is trying to output a programmed voltage,say 10V and the current limit is reached, then the unit goes into a constant current mode. This means the current is at its limit that is programmed by the user and the voltage now varies.
If you truly need a constant current source then I would suggest either the Model 6220 or any of the Keithley source meters (Model 2400 or 2600 series).

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