which NI devices should I buy and how to start with?

[godpaul]

Greetings!

I am an undergraduate who is trying to design a control system which can measure chemical solution conductivity as well as PH value; besides, based on those values, we need to control 4 valves to open and close so that acid, base, water,and salt from 4 tanks can flow into the main pipe.

Question: Which NI device should I buy and start with? The devices have to have at least 4 input/output, do you have any suggestion, Thank you very much!!

I am also new to LabVIEW, so any extra suggestion would be greatly appreciated!

[S1ack]

You have good timing....

$1,499 (USD) Limited Time Offer for NI LabVIEW With NI cDAQ-9174 4-Slot USB Chassis

[godpaul]

thank you but can that measurment device connect Solenoid Valve and send pulse to command it open and close? If so, what kind of output? 12DC or 12AC or something else?

[S1ack]

You populate the rack with modular I/O to your requirements.,

[JarleEkanger]

There is also the myDAQ system available at very cheap for students. It is very basic, with 2 analog inputs, 2 analog outputs and 8 digital input/output lines. But it might meet your imediate needs. You can find more info here.

The cDAQ system suggested by a previous poster is a much better option in the long run, provided there is funding for new I/O modules. However, you will be able to aqcuire from both devices simultaneously, should you decide to start with the myDAQ and buy the cDAQ later.

Note: I suggest the myDAQ on the assumption that the solenoid valves will be operatable by the digital output channels, i.e that they are "binary valves".

[User002]

You can perhaps try out the embedded version of NI's RIO platform.

http://sine.ni.com/nips/cds/view/p/lang/sv/nid/205721

Br,

/Roger

[godpaul]

Thank you for all your advice, by the way, right now I am learning labview using the book which is labview for everyone, making programing easy and fun, is it a good start to begin with?  Any other outside resource that I can refer to, especially for the complex hardware system I will be dealing with 🙂 Thank you

[apok]

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@godpaul wrote:

....measure chemical solution conductivity as well as PH value... we need to control 4 valves to open and close ...

---

to measure:Analog Input

to control: Dig Output

Major Differences Between E Series, M Series, and X Series DAQ Devices

and look at NI LabVIEW 101

also, LabVIEW Templates and Sample Projects 

[godpaul]

Thank you , we are considering purchasing NI USB-6008

http://www.ni.com/products/usb-6008/

Doest it work with the following PH sensor, one specification says that it has output voltage of Output 0-5 vdc, does NI USB-6008 accept it?

Model A1004 pH Transmitter
Warning
Do not short the power connections. Wrong wiring of the signal and power wires will result in
permanent damage to the unit instantly.
Specs:
Range 0-14pH
Power: 12vdc 500ma nominal
Output 0-5 vdc
Material ABS
Calibration trim pots
Distance up to 50ft
Model A1004 is a pH transmitter designed to be used with PLCs and microprocessors that accept
analog input of 0-5vdc.
Connect any general purpose pH sensor to the transmitter. Double junction sensor is preferred.
Calibrate unit with 4 and 7 pH buffer solutions. Use zero trim pot to adjust 4pH and span trim pot to
adjust 7pH..Fine tune adjustment is done with span trim pot.
If you do not have a sensor , short the bnc connector ,this will simulate 7pH and observe output voltage
of 2.5vdc.
Din connector provides power and signal from one cable.

Note.: When connecting signal and ground to the PLC input ,use .01uf capacitor across signal
and ground to filter any noise issues.

[ajmartin]

The 6008 analog input will accept up to 10V, it is a nice cheap DAQ and should do fine for your application.

Alan