Right harware to control proprtional solenoid valves

[bayram_mercan]

Hello,

i am trying to control 10 proportional solenoid valves for my master thesis.  i want to control each valve seperately. for example i will give a sinisodial function to every valve. the valves work with pwm signals (0-24V DC). i have ni c-daq 9172, 6 slots still empty. now i have to options to control the valves:

1. buy the controllers of the valves and an analog output terminal for c-daq 9172. the controller of the valves can convert analog input to pwm signals.

2. buy a digital output module for c-daq 9172.

i think second option will be cheaper. but i can not find the right module. can you help me?

thanks,

bayram

Message Edited by bayram_mercan on 07-30-2009 05:10 AM

[Mark_SAI]

Hello,

Please look at this product selection guide.

Can I recommend that you discuss your requirements with a sales engineer over the telephone, details here

Considerations are:

Speed of digital outputs (1us = 1mhz, 500us = 2khz), this will determine PWM speed.

Current, as the module will be directly driving the solenoids. 

Sinking or Sourcing will determine the configuration of your wiring.

Message Edited by macaba on 07-30-2009 05:43 AM

[Mark_SAI]

Hello,

This may also help!

[bayram_mercan]

i've looked at the c series digital output modules pdf. in this document it is written:

" For instance, with CompactRIO you can implement a circuit to generate
pulse-width modulation (PWM) outputs for controlling motors."

but i have c-daq. does this make a problem for creating pwm signals?

secondly,  in logic column what does "high voltage", "form a" and "ssr" mean?

thank you,

bayram

[Mark_SAI]

Hello,

I have just tested the attached VI on a cDAQ-9172 with a NI 9401 module (this module isn't a good choice for you, as its TTL but its similar to the ones you are looking at), and it worked very well.

Form A uses an electromechanical relay, SSR uses Solid State Relays.

[bayram_mercan]

Our aim is to control the valves directly by a PWM signal generator hardware from NI.

I have found NI 9472( 8-channel, 100 µs digital output, 24 v) device to be compatible with NI cDAQ-9172. 

Now, the question is" can we attach two NI 9472 to cDAQ-9172 to have 16 channels for PWM signal generation?"

and secondly, can the duty cycle of the signals be driven by time dependent functions(as sine waves or etc) in LABVIEW program?

Thanks for your help,

Bayram

[bayram_mercan]

hello,

i have another question.

 http://digital.ni.com/public.nsf/allkb/24BFC7D0AB91D9248625711F005806F4?OpenDocument 

in this page it is indicated that NI 9472  is supported in the USB-9162 carrier for NI-DAQmx. is this mean we should also buy USB-9162? and if it is neccessary where shopuld we connect this usb port? i mean if we buy USB-9162 i understand that NI 9472 will not be connected to c-DAQ 9172! ?

bayram

[HeatherBaker]

Good afternoon,

You can put multiple NI 9472 into the chassis to increase your channel count. Versatility is one of the things that makes cDAQ so useful!  I think this chart is easier to read about compatibility.  The NI 9162 is the single module carrier option to the NI 9172, thus you will not need to purchase a NI 9162 for this application. 

Can you please elaborate more on what you mean by driving duty cycles with time dependent functions?

Have a nice weekend!

[yashar ostovan]

Hi,

Mr. Mark, I would like to thank for your useful replies.

I am BAYRAM's colleague in this project. before starting this forum I have been in contact with one of the other engineers from NI. He is mentioning about a problem that Only 5th and 6th slots of cDAQ 9172 support counter output signals. Supported counter output is only 2 channels, so he means even if we have two NI 9472 we can just have 4 counter out put signals! now, we are a little bit confused! 

I will appreciate if you can make a clarification about this problem.

Special Regards,

Yashar Ostovan.

[yashar ostovan]

About the Duty cycle,

We want to drive the valves separately by various functions as( harmonic, linear and etc). So we should be able to define our PWM signal's duty cycle by this functions. For example:

Duty cycle = Sine(t) and t is time.

Regards,

Yashar ostovan.