Solenoid Control for Water Flow

[Andy_thesai]

Hi there!

I need to develop a program using labView to control the flow using solenoid valve (SMC VX3344-03T-5DS1-B) as water flow valve. What I currently have is NI9266 and NI cDAQ-9188 chassis.

However, I am a newbie in this environement and don't have no clude about the labView related knowledge at all, so, I've no idea which direction should I go to. So, I'be very thankful if anyone guide me the learning path and ideas to make it happen.

Thank you so much. 

[GerdW · Accepted solution]

Hi whatever,

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@Andy_thesai wrote:

I need to develop a program using labView to control the flow using solenoid valve (SMC VX3344-03T-5DS1-B) as water flow valve. What I currently have is NI9266 and NI cDAQ-9188 chassis.

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The NI9266 is a current output module, suitable to drive 0…20mA with a compliance voltage of 12V.

The solenoid is operated at 24V and most probably needs way more than 20mA.

I guess you should start with reading datasheets/specs for your (currently available) hardware, consult a electrical engineer in your department and order suitable hardware that fits your requirements!

When it comes to software you should learn LabVIEW by those Training resources offered at the top of the LabVIEW board. (And also learn how to spell LabVIEW… :D)

[D.VA · Accepted solution]

Help > Find Examples... (This launches the NI Example Finder) or

https://www.ni.com/examples/

In the example finder, you can look through a library of examples. For your application, you'll probably want to look at:

Hardware Input and Output > DAQmx > Analog Output 

Hardware Input and Output > DAQmx > Digital Output

There's also an abundance of previous forum posts with similar issues. If you put "solenoid control" into the search bar, and go to community, there's plenty of other people with similar problems you can pick ideas from. 

https://learn.ni.com/
There's plenty of courses here to help you get started, depending on how new you are. 

Learn LabVIEW, get stuck, come back with code that has a problem. 

[rolfk · Accepted solution]

A valve is an on/off device, your DAQ output is an analog current.

Your valve needs 24V DC/10.5W to operate, that is almost 440mA of current flow in activated state.

You need a relay or solid state relay output to activate your valve, not a current output!

[Kyle97330]

Are you by chance stuck using leftover or surplus devices?  What sort of budget or options for extra equipment do you have?

I ask because the 9188 was superseded by the 9189 in 2017.  Not that there's something magic about the difference between the two, more that it seems like there's very little chance you're using equipment that was ordered specifically for your task.

[Andy_thesai]

I would say leftover one. I was told like we have this and that so you gotta use them for the system. 

However, I need to make it happen at least. Speaking of budget, I've considerable amount of budget about 2000 USD for this work. Kindly suggest me if any possible things I can do. 

Much thanks 

Andrew

[rolfk]

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@Andy_thesai wrote:

However, I need to make it happen at least. Speaking of budget, I've considerable amount of budget about 2000 USD for this work. Kindly suggest me if any possible things I can do. 

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Well under these conditions there are definitely a lot of options!

You could buy a NI 9472 and control your valve with that. This module has eight digital outputs that can drive loads with up to 0.75A per channel (although there is a total current limit that is smaller than 8 times 0.75A). Just make sure to use a flyback diode across the solenoid valve if it isn't already internally equipped with one. That solenoid tends to create a considerable backwards EMV when switched off, that can reach easily 3 to 4 times the operating voltage and eventually damage your digital output, if not properly neutralized.

Another option would be to use an external SSR relay module that you control with a normal digital output from one of your modules. But while that might cost a little less if you only need to control one solenoid (and you have an according low power digital output available), it means more external wiring and generally a less clean test setup unless you have already a nicely designed e-cabinet with DIN rails available. And for the price of the 9472, you really can't spend a lot of time, trying to find other cheaper hardware and do extra wiring work.

[SteveD123]

You have a 4-20 mA output. This will generate 2.4 to 12 V across a 600 ohm resistor.

Use a CMOS Schmitt trigger (e.g. Texas Instruments CD40106B) to trigger about 5.9v which is about 10mA output from your NI device. Feed this into a solid state relay to drive the solenoid.

Remember your freewheeling diode across the solenoid.

Remembetr to tie all unused inputs on the CD40106B to 0V.

Reccomend using a seperate PSU for the solenoid, so that your instrumentation is not affected by the transients as it turns on and off. Also allows you to wire in an emergency stop that is not dependent on your software, if required.