LEVEL CONTROL - VALVE PROPORTIONAL

HI
I want to change some file.
Can you help me.
Of labview 8,5 to labview 8,2.
files are attachments
Thanks
Attachments:
Jadi.vi ‏47 KB
limitter.vi ‏9 KB
PID.vi ‏35 KB

LV8.2
Attachments:
JadiLV82.vi ‏47 KB
limiterLV82.vi ‏8 KB
PIDLV82.vi ‏30 KB

Similar Messages

Controlling a proportional control valve

Hi,
I wish to control a the flow of air through a pipe using a proportional control valve. I also what to feed back the flow rate with an anemometer. I'm using labview 8.2 and i'm not sure what sort of DAQ card i'm using. I'm a novice with LABview to say the least so any advice in the right direction would be greatly appreciated. Thanks in advance.
Regards
Josh

I don't think a motion control system is necessary. However, you'll need to provide more information about your system in order to get a helpful answer. Do you already have a data acquisition card, and if so, can you find out what it is? If it's a National Instruments card, and installed in your computer, try opening Measurement and Automation Explorer (MAX) and see what device you have. Do you already have the other components of your system: the proportional valve and the anemometer? If so, what sort of signals do they need and provide? How much accuracy in your control do you need? If you don't already have your valve and meter, have you considered buying a flow controller that already includes both a valve and a meter in one package (I've used Mass Flow Controllers from Brooks Instrument, other companies offer similar valves)? While such valves aren't cheap, you can simply write a voltage to it corresponding to the desired flow, and read back the actual flow rate.
Message Edited by nathand on 02-12-2009 08:49 AM

Level Control with PID Control & Pulse-Width Modulation

Hi all,
I have attached my program which I'm having trouble wiring up in the block diagram.... I'm fairly new to labview, but basically I have a level control project with an analog input cistern arm turning a pot for my test tank (configured as DAQ assistant voltage analog i/p) and a pump working off a reservoir (configured as DAQ assistant voltage digital o/p). My electrical side of things is working correctly and I have tested both DAQ assistants I/O's successfully off a basic program, minus the PID & PWM... I found a simple PID control subvi which I think I have wired up correctly, apart from the output variable... I also found a bit of code for PWM using the square waveform vi (far right side of the program) which I have tried to include in the program, but I've been unsuccessful with that. The ideal operation i'm looking for with this project is to be able to enter different values for the setpoint, for the PID to kick in to find that setpoint each time using the PWM to drive the pump, which has a flow rate of 13L/min. I have a manual valve to release water from my test tank which I can set accordingly.
My questions are;
- How do I connect the 'output variable' of the PID subvi to my DAQ assistant digital output(both DAQ assistants are set at 1 sample on demand)?
I have a 'number to boolean array' function, but this gives an error saying that the number of tasks generated are not the same...
- How do I wire up the PWM bit of code? Do I need to include the 'error in & out' tabs?
-Am I on the right track with this program or am I way off the mark?!
Any feedback on this would be greatly appreciated. Thanks for your time,
Richie
Attachments:
PID-RichLevelControl.vi ‏91 KB

Rich-MechatronicsStudent wrote:My questions are;
- How do I connect the 'output variable' of the PID subvi to my DAQ assistant digital output(both DAQ assistants are set at 1 sample on demand)?
I have a 'number to boolean array' function, but this gives an error saying that the number of tasks generated are not the same...
- How do I wire up the PWM bit of code? Do I need to include the 'error in & out' tabs?
-Am I on the right track with this program or am I way off the mark?!
You're a bit off track. You need the output of the PID to go into the PWM generator, and the output of the PWM to be written to the digital output. Right now you have the output of the PID connected directly to the Digital Output in a way that won't work, and the PWM generator hanging off the side not really connected to anything. Also, the PWM generator isn't really going to work since you're generating it at the same frequency as your PID loop runs. Try a simpler algorithm such as on/off control first and see if that works for your system.

Level control

Hi Everybody,
I am new to Labview so I am looking for your help. I am looking for the most basic control diagram for a PID level control circuit.Thanks.

Moonlight, at it's simplest, PID control works by operating on an error signal,or the difference between the desired output and the current output.
So, in order to implement PID control, the first step is to calculate that process error.
Second, you now need to multiply that process error by a proportional (P) constant, an integration term (I), and a differential term (D). Then add up those products.
There are MANY ways to do the integral and derivative terms, so I will leave that to you. Search for PID on the NI website, and you will find at least one example of how to do it.
Good luck,a nd I will repost later with some examples.
Wes
Wes Ramm, Cyth UK
CLD, CPLI

Control valve resonse time measurement

I am a new student in control valves.I am using control valve to control the liquid level by controlling the flow using control valve.I Want to know the response time and time constant of the control valve , I do nt have any idea how to do it,any bodyhave any info about it or any link where i can get some relevant informatiom.
Regards
Dost

You will need to do some transient measurements.
You can suddenly open your valve and measure the flow rate increase in time and
can derive the time constant by doing measurements with different inlet
pressures and valve settings. But normally valve producers are providing this
information. May be you should first look at the documents of the valve.

Control valve logic?

I need to control the valve with Labview
I am using DAQ 6251, PXI 1031.
Please let me know, how can I develop the VI.
I am attaching the specification of the control valve.
Attachments:
Actuator-irehcontrols20110330CNP1LAL.pdf ‏2245 KB

So you will need some kind of amplifier/level shifter/current source circuit as an interface between your DAQ device and the valve.
I am still confused or how can I choose the amplifier/level shifter/current source as per DAQ 6251.Please see the attached manual of the valve.
Attachments:
Actuator-irehcontrols20110330CNP1LAL.pdf ‏2245 KB

How to get the position of the stem in control valve using slider control in the front panel

I have created a calibration program for a control valve. Signal (4-20mA) is generated from labview using slider contorl which is given to the valve via DAQ(module 9265) and again the feedback signal from the valve is acquired using DAQ(module 9203).. . There is an input ISO/ISC(Increasing signal to open/ Increasing signal to close) in the front panel.
ISO would set the output to increase from (4-20)mA further opening the valve
ISC would set the output to increase from (4-20)mA further closing the valve
I have doubt, how can i get the position of a stem

Ravens Fan wrote:
If the position of the stem is being sent to the PC through a 4-20 mA signal into your DAQ 9203 module, then you just need to do an analog input read in order to get the signal.
When reading this post, that is what came to mind... So let's see if both RavensFan & I are trying to understand the same thing... Are you saying that the position of the stem is linear (or scaled) to the amount of current sent to it? Meaning a 4mA signal would move it a certain distance, and 10mA would move another given / known distance? Or are you saying that it is calibrated so that a 20mA signal for a certain duration (ms) would move it a given distance? So the scale would be time and not current unless a lookup table is used to adjust the time duration based on the current being drawn...
It's just that I am not familiar with solenoid / drive devices that related to current.. To voltage, yes. To time, yes.. To current, I'm simply saying that I am not familiar with that. Can you tell us more about this stem (mfg / model designation)?

No zoom level controls on second monitor!

I use a second monitor to display a loupe view of the photo I have selected in the grid view, which is on the first monitor. I have always had the zoom-level controls (Fit, Fill, etc.) at the bottom of the loupe display on the second moitor, until I replaced my first monitor this week. Everything else is still the same, but I no longer have the zoom controls on the second monitor. This means that I cannot change the zoom levels that are availabel to me. I either have Fit or 100% zoom. Without the zoom controls on the second monitor I can't change the settings. Does anyone know how to get the zoom controls back (or why they might have disappeared)?
Thanks for any help.

Never mind. I found the problem (the second monitor was in full-screen mode). Nothing
to see here. Keep moving.

Control valve program

Hello dear member of the forum,
1st of all let me tell you all that i am very new to labview i just know the basics.
i am experimenting with a control valve: of LEE LHL series whose specs are asa follows
3-way HDI (High density Interface)
5 volt models
10 ms maximum for switching states
i am using NI-USB 6501 controller for these valve, i need to use 3 of the above control vales to operate at same time.
i had done a VI in labview 8.6, but it seem not be working so fine, it does not run at all. i would also like to know if i can know the postion of the valve by placing some graphic indicator?
i would like to upload the VI that i had done, can you please tell me how to upload the VI
thank you
rgds
Rajan

The first problem is that the your Case structure selectors are unwired (that's why your run arrow is broken - I wired them to your activate buttons), but that's not your only problem... I also put each section in its own While Loop.
As a first pass, take a look at what I've done. It'll take a lot more work to do what I think you finally want, but this should get you running. Your controls will stay on as long as the valve is closed, as you specified.
Study up on State Machines and Shift Registers; you'll need to do that if you want a maintainable program. It's really ugly to have a separate loop for each valve. Write back with any questions you come up with.
jim
Jim
You're entirely bonkers. But I'll tell you a secret. All the best people are. ~ Alice
Attachments:
valve_1[1].vi ‏31 KB

Tank Level Control with PID regulator

Hello!
I found a lot of examples regarding the simulation of a tank - level control with PID regulator. but I still have a dilemma.
I can't find the transfer function for the process, if you can help me it would be great because I'm stuck here...

Maybe you could ask some of you classmates?
LabVIEW Champion . Do more with less code and in less time .

Automatic Level Control.

I am transferring stereo audio cassettes into GB. I noticed that when I check Automatic Level Control, it always goes to 75%. Does this just start there and manually ride the audio or is it "smarter" in a digital way. I think the results with the auto level "on" sound good so far but I noticed a few sudden volume drops here and there. I am not sure if they came from the Auto Level. It's hard to find the exact spots on tape to compare since I've transferred a few hours worth already. Do I need to go back and just set my own levels? I do want to best possible copy. If so, can let it hit red on the peaks? (I don't hear it distort on the short peaks but I'm monitoring with crummy speakers now) Thanks!

In case anyone is curious, the Auto Level is not for quality recording. It was jumping the volume around after all. Be careful of this. That's how you learn a new program I guess I wanted to redo some other stuff anyway so no big loss.

Overriding Processor audio level controls

Hello,
I'm developing an application to capture a live audio stream (by definition a PushDataSource). I want to provide my own controls for monitoring the audio (e.g. mute button, volume level control). What methods set the volume level? I didn't see any of this in the documentation.
I saw getGainControl, but I want to provide my own ... just setting the gain.
Is there an example of this?
Thanks,
Ben

brcain wrote:
Do I have to implement a GainEffect plug-in ... just to change the monitored audio level?No. You can actually implement the controls on the PushDataSource itself.
For instance, I have the following code available on the forum:
[http://forums.sun.com/thread.jspa?forumID=28&threadID=5342704]
That code will capture audio using JavaSound, and deliver it to JMF via a PushBufferStream. Because the capturing is done with JavaSound directly, I can run any kind of JavaSound processing I want on the audio before I hand it to JMF.
I could, for instance, convert it to ULAW before I give it to JMF...
[http://www.jsresources.org/examples/UlawEncoder.html]
I could, for instance, change the sample rate before I give it to JMF...
[http://www.jsresources.org/examples/SampleRateConverter.html]
I could, in particular, change the volume before I give it to JMF...
[http://www.jsresources.org/examples/AmplitudeConverter.html]
All you're handing to JMF is a set of audio samples. You can adjust them or monitor them however you want before you give them to JMF...

Need a multi-level control break report displaying a cross-tab for each ...

I need a multi-level control break report that displays a cross-tab report for each
detail and subtotal. The individual cross-tabs are no problem. There are two issues:
1) How to get many cross-tabs (thousands) to appear in one report.
2) How to provide cross-tabs in-line on the multi-level subtotal lines.
Here is a concrete example.
Suppose the data base contains this table:
road (
id_number number, -- this is an artificial PK
city varchar2,
county varchar2,
state varchar2,
length number,
owner varchar2, -- roads may be owned by cities, counties, states, and others
surface_type varchar2 -- the surface type may be gravel, asphalt, concrete, and others
The table is populated with several million records that include every
length of road in a US city.
It is OK to suppose that all the attributes in all the records are not null.
Without the PK, there would be millions of duplicates,
which should all contribute to the summed lengths.
The report I need is like a control break report with a detail line for each
city together with subtotals for each county and state and
a grand total for the US at the end.
However, each detail and total line needs to be a cross-tab report
summing the length over the city, county, state or US
(whichever is called for at that location)
for each combination of owner and surface_type.
so the report would have the following structure:
a city cross-tab for the first city in county 1/state 1
a city cross tab for the last city in county 1/state 1
a cross-tab for count 1
a city cross tab for the first city in county 2/state 1
a city cross tab for the last city in county 2/state 1
a cross tab for state 1
a cross-tab for the US
Any suggestions will be appreciated.
This problem comes up because my client's legacy system,
which is being replaced,
already has such a report (in COBOL).
Thanks!!!
Steve
PS, I know one ugly way to do it. Namely, make a variable for each
possible combination of owner and surface. Then code an ordinary control
break report. However, I am looking for something better.

Hi Jenna_Fire,
According to your description, you have a matrix contains total for each group on each level. Now your requirement is, when you click on any number (data field or total), it will go to the detail report which returns all the detail information of the people
within the group scope. For example, if you click on the total of Active users in United States, it will return the detail information of Active users in New York and Texas. Right?
In this scenario, we should set the parameter (@Country, @State, @City) allow multiple values in both main and detail report. And in Default Value (@Country, @State, @City), query out all distinct values. In the textbox which contains
those total values, when set use these parameters to run the report, we only need to pass the parameters of parent groups. For example, if we click on the total of Active users in New York, we only need to pass Country, State, Status to detail report, and
in the detail report, the City parameter will use all distinct values (Default Values) because we don't pass the City parameter. We have tested this case with sample data in our local environment. Here are steps and screenshots for your reference:
1. Create parameter Country, State, City and Status in both main report and detail report. Set both Available Value and Default Value get values from query (Create a dataset for each parameter, use "select distinct [column] from [table]" as query). Set allow
multiple values for parameter Country, State and City in both reports.
2. In corresponding textbox, pass appropriate parameters in go to report Action.
4. Filter data in detail report (in where clause or using filters).
5. Save and preview. It looks like below:
Reference:
Using Parameters to Connect to Other Reports
If you have any question, please feel free to ask.
Best Regards,
Simon Hou

Manual Audio Level Controls! - Sony Alpha DSLRS (A65)

Dear Sony -I absolutely love your DSLRs. However, to use the camera as an acceptable tool for amateur/indie/professional film, manual audio level controls in video mode are a must-have. Equal Canon competitors all feature this simple leveling option for managing audio.Currently, the automatic gain control is the only option for audio recording capabilities on Sony Alpha DSLRS in video recording. While in theory OK, AGC leads to terrible problems such as unnecessarily high and distracting background noise/hiss. Filmmakers desire crisp, clear audio!For quality results using an external microhpone, manual audio levels are the only way for filmmakers to achieve decent in-camera audio to compete with Canon users. Many amateur and professional videographers are in desperate need of this function! Audio is often MORE important than the image quality of your film, although Sony seems to increasingly neglect its video DSLR users by not implementing this ability and falling short on video options (Auto-focus in Manual Mode, audio levels on HUD etc.).To keep my Sony A65 a viable option for video work - please see if anything can be done! (Should be able to be added with a firmware update to all current and existing Alpha DSLRS) Thanks!!! - Love, a filmmaker who would desperately like to keep their A65 for professional video work! (Also from "Join The Inspiration")

Though a great idea, you also have to understand that the a65 isn't as film oriented camera like other cameras.
DSLR cameras with the audio controls are designed with film making in mind, thus they have that option.
Most DSLRs (at least, back in the days) was simply a camera to take photos. If you wanted to do film, you'd buy a dedicated film recorder for that. Having video capabilities in a DSLR was a bonus.
Nowadays, it's merging, bang for buck, reaching to a boarder audience, one size fits all, etc, and unfortunately, the a65 wasn't part of that 'nowadays' era.
The a99 and a77ii, if I remember correctly, has audio controls.
A lot of the newer Sony models (mirrorless) also have audio controls, that is, the ones that a targeted towards film making and not just great photos with the bonus of great video.
Also, I would presume that a lot of 'professional' videographers will either use external mics such as on a pole, a lapel mic, etc, to capture perfect audio, or if not, at least a shotgun/boom mic attached to the camera.
When doing such, there technically shouldn't be a lot of problems with the audio quality. Of course, if those external mics are still recorded into the camera, then yeah... but if they're recorded separately and slapped on during post processing... shouldn't be any problems...
If you're relying purely on the a65 and it's AGC, then there definitely will be shortcomings here and there unfortunately.
I recently filmed my niece-in-law's wedding. I didn't have any fancy mic setups (can't afford it at this stage), and this wasn't any sort of 'professional' work, more of just something for the family (free), but the audio came out excellent. Yes, it caught ambient noise (obviously), but I don't hear any cutoffs or badly pitched noises, or anything. The loud music and people cheering on and such all came through very clearly. Sure, it's no 'professional' bitrate or anything, but at 192kbps, it did the job.
Anyways, that was off topic, but all I'm saying is, you can't expect much from a photo taking centred camera which has been slapped on with nice video capabilities unfortunately. Also, due to the a65's age, I don't think Sony's bringing out anymore updates. My advice is either get an a77ii for it's awesome AF, or if full frame is a desire, then the a99 or a mirrorless (up to you).The a99 has a controllable focus range which is something I like, that way, if you're using autofocus (yeah... what 'professional' videographer would use autofocus aye?), you won't lose focus on subjects if something goes in front/behind it.Also, the little wheel at the front really helps in allowing you to make adjustments without disrupting video or causing too much movement in the camera. Right now, I am planning on getting a RX10ii. Though I'd love to get something from the mirrorless range, it's just way out of my budget (even the RX10ii is, so there's a lot of saving to do right now also...). Anyways, good luck with your videos.

Auto level control working even though unchecked?

Greetings,
One of my singers is cutting tracks for me using GB 6.0.5. He has the Automatic Level Control checkbox unchecked, but says that the volume slider is still moving all over the place as he sings. Any idea what could be causing this?
Thanks,
DM

That slider should indeed only move with " Automatic Level Control" enabled; perhaps the preferences file is corrupted. Try HangTime's cure for "Oddball" problems and remove the GarageBand preferences and repair permissions:
http://www.bulletsandbones.com/GB/FAQPages/OddBallProbs.html
Regards
Léonie
P.S.
Are you using Mac OS X Lion or later? Then your user library is hidden. You open it best from the Finder's "Go" menu, from the main menu bar:
Go > Go to folder then hold down the alt/option key until the library appears in the drop down menu. Select it to open.

LEVEL CONTROL - VALVE PROPORTIONAL

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