How to control solenoid valves ?

[kishan07]

I need to build a system where I have to control 4 or 5 small solenoid valves independent of each other using LabVIEW.

I have two options: 12 V DC, 2W or 12/24 V DC, 6W.


I am really new to LabView and interfacing. So this may sound dumb:

1.Do I need Arduino or some other kind of embedded system for controlling the valves? Or labview has some kind
of module for that?


2.Will each of the valves need separate power source?


Any suggestions are welcome. Thanks

[martin_g]

You need to use a relay that can switch thst voltage & current. The NI 9478 is good for switching solenoids, some of my clients have used it to switch 2 million cycles without any problems.

Cheaper option: NI did a USB solid state relay card that couls switch 24v up to 0.5a - USB6525

Alternatively use a TTL output device and pick some relays that will switch the load

[Tim_S]

1.Do I need Arduino or some other kind of embedded system for controlling the valves? Or labview has some kind

of module for that?

2.Will each of the valves need separate power source?

 

1. You will need some sort of hardware that the software (LabVIEW) talks to. National Instruments sells a variety of hardware that works well with their software. There are other hardware (the Arduino you mentioned is one) that would give you the same ability to control. What hardware you pick (and how you control it) is dependent on what your other requirements are. Do you need to switch within seconds, milliseconds, or microseconds? What is the load rating (looks like you have that)? Etc...

 

2. Separate power sources is a controls issue. If you have power supplies only capable of handling one solenoid with inrush current, then yes you will need separate supplies. If you have one supply capable of handling all three with inrush current, then you're fine with one. There is also the impact from a safety risk analysis.

[ned]

Also note that any time you connect a solenoid valve to a relay, it is a good idea to install a flyback diode as well.

[ElectricWraith]

You have a couple of options, and in addition to what's already been posted I'll add the following:

1. Since your solenoid options appear to be 12 or 24V, you're stuck with industrial logic levels (unless you take the aforementioned intermediate step of using a TTL driver & compatible relay), so look at NI's industrial logic-capable DIO modules, they have lots.
2. No matter what approach you choose, your primary concerns are the current and (as ned points out above) inductive kick. I'll add to his statement by saying NEVER drive an inductive load from a digital output without a flyback diode. You WILL destroy the output. Period.
3. Once you know what your drive currents will be, make sure the DIO module you're looking at can handle them. Most of the relay modules will switch those currents easily, but they're dry contact relays, so you'll need to connect an external power supply to the relay module COM inputs.
4. There are many basic digital output examples available in the Example Finder. Once you have your hardware all connected and verified (don't overlook this step!), it should be a snap to customize one of the examples to match your digital output connections.