i2dx

a big "Thank You" to NI and AQ! ... this makes me really happy

QUOTE (fuzzycontrolfreak @ Mar 17 2008, 01:41 PM)

Hi there,

I am designing a simple data logger for an industrial application, and it seems that the USB-6008 has all the specs needed for my measurements (accuracy, resolution, no. of channels, and sampling rate). I just fear the fact that this is a low end card, and that it might not suite the harsh industrial environment, especially its image as a school lab card.

Are there any durability/stability issues regarding the use of the USB-6008 in an industrial environment, just for data logging, knowing that all the specs are compliant to the application, and that we have no problem with the USB conection.

Thankyou so much for your help...

if you are searching for a ready to run datalogging application based on LabVIEW / NI-USB-6008 / Access Database http://www.ib-berger.com/index.php?action=ibblogger' rel='nofollow' target="_blank">you should check this one

QUOTE (jlokanis @ Mar 14 2008, 01:33 AM)

Is there another solution entirely that I could try? All I need to be able to do is pass a SQL query to the DB and get back a record set.

maybe you want to try out my ADO-Toolkit?

(the link is in my signature ...)

cheers,

CB

QUOTE (Klaus Petersen @ Mar 4 2008, 10:06 PM)

My problem is that i'm using the ADO-toolkit to connect to a database. But apperently this relies on the host having MS access installed to work.

that's wrong. the ADO-Toolkit does not need Access to work properly

QUOTE (rolfk @ Mar 10 2008, 09:52 PM)

that's right. You have to install MDAC to use the ADO-Toolkit. MDAC is allready pre-installed on Windows 2k or higher, so you have to install it on Windows 98 or if you want to update your MDAC installation

QUOTE(PeterB @ Mar 10 2008, 10:27 AM)

Is the following point the most important requirement they can muster to the top of their "http://lavape.sourceforge.net/doc/html/Unsolved.htm' target="_blank">Urgent problems in current programming languages" list ? If so then perhaps we should really feel sorry for them as they acknowledge their text based state of the art languages are still in the dark ages.

1. Programs should no longer be "written"

It's time to finally overcome the antediluvian technology of software production using text editors. Programs should no longer be "written" but constructed/composed in Lego-like fashion from basic constructs, using

structure editors

rather than text editors. Particularly the executable portions of programs are the last bastions of textual programming that remain to be captured by

"point-and-click" technology

.

pah, that's marketing mumbojumbo.

If this should "work" there has to either be ONE complete architecture from the bottom of all software to the top for ALL the software which is written in the future or the superduperueberversatileerrorcompensationg virtual standardized interface - and that's absolutely unrealistic. If software is no longer programmed, but constructed, this implies, that the framework you compose your software with is able to solve all software problem, now and forever.

Just to go a little bit further: If all software could be *just* composed, that would mean:

1. mankind has reached the point where creativity and genius is obsolete

2. you could automate the software creation process ==> which means, if software can create all the software, it has it's own consciousness and you know what that means ... (I hope you saw Terminator 3 ...)

sad but true: lava.org isn't the one and only really hot thing on the planet any more ;(

QUOTE(Aristos Queue @ Feb 15 2008, 10:29 PM)

That's why I try never to use hardware. :-)

this explains a LOT

QUOTE(PJM_labview @ Feb 15 2008, 12:39 AM)

Since we are on the topic of "hardware" wish list, I want a cRIO with optional FPGA back plane. I want the modules, the processing power, not the FPGA.

PJM

hardware whishlist?

here comes my favorite: a NI Atmel AVR Device plus the LabVIEW AVR Module!

that should not be that difficult, because there is an Atmel AVR working inside the LEGO brick and there is already a toolset for it.

Those devices should be able to commuicate through RS232 or TCP-IP or CAN or SPI, to allow the development of "deeply" distributed systems. And hey, that rides directly on the multiprocessing wave

QUOTE(tcplomp @ Feb 14 2008, 09:37 PM)

Can someone explain why I was thinking of Rolf of I2dx?

Ton

hmm ... I dunno ... maybe I look like THAT when I'm dancing? (And I swear I don't do this often!)

QUOTE(Anders Björk @ Feb 14 2008, 09:21 AM)

A bit but not, but without the processing capacity.

yes, that's cRIO:

http://zone.ni.com/devzone/cda/tut/p/id/6265

just forget about the high volume

QUOTE(Aristos Queue @ Feb 13 2008, 11:28 PM)

[...]

So OF COURSE handling as variant is substantially faster. Why? VARIANTS AREN'T FLAT. The data is picked up off the wire whole, with all the hair hanging off of it (arrays of clusters of arrays of clusters of arrays of... etc) and put in the variant along with the type of the wire. Then when we convert it back to data, there's just a check that the type descriptors are compatible and we're done. When flattening to a string, there's the whole traversal of the type descriptor to create the flattened string and then unflattening requires not just traversal of the type descriptor but also parsing of the string and memory allocation.

You got a 50% speed difference in your test. That's with a simple array. The more complex the type the greater the difference between these will be.

QUOTE(Aristos Queue @ Feb 14 2008, 06:29 PM)

Thanks a LOT for pointing that out. Why? ... that statment saves me a lot of time for benchmarking my data transfer mechanisms in my distributed systems

QUOTE(Gabi1 @ Feb 12 2008, 09:53 PM)

A little bit. i use magnetic coils and high currents.

are you offering me a job? :laugh:

[...]

7) good luck! but arent you more of a Labview guy?

WHOW, thanks a LOT!

maybe I could offer you a job, but it's a long way until then. First I have to write my business plan and so on and so on ...

--> 7.) yes, I am a LabVIEW guy, and more severly: I know allmost nothing about how to build a circuit. Ok, it's still enough to impress my little sister, but I'm an absolute no0b compared to an "interested amateur".

If there is allready any finished solution which can act as a frequency converter circuit (20 kHz base frequency, 1-35V, 0-150A, 0-240 Hz) and create a 3 Phase rotary field for AC motors, and HAS DIRECT ACCESS to the MOSFETS/IGBTS through digital inputs, please let me know. This solution has not to be able to convert the Voltage, I just want to switch the current. All finished solutions I could find so far are "ready to run" frequency converters with it's own µC, but I want to control the frequency by myself (in my FPGA VI)

QUOTE(snooper @ Feb 14 2008, 04:03 PM)

Hey,

Is there any LabVIEW database user that is willing to share their experiences with this product? or maybe with using databases in general?

With kind regards,

Arnoud de Kuijper

hmm ... maybe the response to your solution is so small, because there are already 2 (or more?) established free Database toolkits for LabVIEW.

The first I know is http://jeffreytravis.com/lost/labsql.html' target="_blank">LabSQL from Jeffrey Travis

the second one is the one I wrote: ADO-Toolkit (the link is in my signature)

which supports (for free) and is tested with: Access, Excel, MSSQL, mySQL and should support (but not yet tested) Oracle and any other Database which can be connected through ODBC.

Last but not least, if you need support (and want to pay for the product): The Database Connectivity Toolset from NI.

I can only speak for myself:I have about 400 - 500 Downloads per month since 2006, the ADO-Toolkit exists since 2005. So I'd consider my toolkit as a renowned LV-Database Toolkit => I think it would be really hard to establish a paid / free but limited alternative to this 3 products ...

QUOTE(AnalogKid2DigitalMan @ Feb 11 2008, 05:44 PM)

If the drive signal orignates from a PC, optical or galvanic isolation would be wise on the input stage of the PWM drive.

Pah, isolation is for cowards That 9401 Module does not cost that much anyway and NI will love me, if I order them in dozens

seroius again: yepp, sounds like a good idea!

QUOTE(Gabi1 @ Feb 8 2008, 10:42 PM)

my salt: this is not a LV question, much rather a hardware one. if you have little experience with relaying, better get the help of an electronician. MOSFETS, and especially IGBTs, are expensive and relatively much more complicated equipment than simple relays. but for your voltage and frequency range there is not much choice. for higher currents as already pointed out you have not much choice but a IGBT. be aware tough, that they require separate power supplys, and that they tend to break very easily if not handled with great care in designing your circuit. for example, if the induced magnetic field is high, then you can expect a 'backcurrent' at turn off of the IGBT, which could lead to a surge of voltage to very high values. IGBTs in general cannot handle more than a thousand volts or so, (not to mention health and risks to living organisms...), therefore should be protected with varistors. These in turn have a breakdown voltage proportional to the current, so you should also look into the datasheet of those and choose them carefully. They also induce a longer shut down time, (depending on max voltage, current and induced field), limiting the overall rate of switching.

to your consideration...

sounds like you have some experience with such circuits?

I'm still searching for someone who could give me a little input about how to build a frequency converter circuit (20 kHz base frequency, 1-35V, 0-150A, 0-240 Hz) which is directly connected to a cRIO 9401 DIO Module (which generates the PWM) ...

QUOTE(rtn1 @ Feb 8 2008, 09:31 AM)

Hey. I am trying to control 200 volts using PWM. I understand that DAQ boards that i know of cannot produce 200 volts so i would need a seperate DC power supply. The only way of turning on and off this 200 volt source using labview that i know of is a relay, but i am wondering if there is a relay fast enough to process the PWM. Is there any other way of varying a voltage as high as 200v using labview? Any information will be helpful. Thanks in advance.

that depends of the base frequency of your generated PWM signal and the switching time of your relays. If your signal is very slow (e.g. 10 Hz) a solid state relay may be fast enough. If you use e.g. 20 kHz (which is a common base frequency of frequency-converters ...) a relay will not be fast enough. In that case you should think about useing MOSFETs or IGBTs, but that is a science of its own.

The ADO Toolkit makes usage of the local computers time format, determined by '%c'.

There are 2 polymorphic Conversion VIs in the ADO-Tool Subpalette, which help you to do the correct conversion. BTW: AFAIK it's the best solution to use always a dot as the decimal separator, because SQL separates the columns by a comma.

Use the "Data to SQL String" VI to convert Data into an SQL string and "Variant to Data" to convert the data from the result into LabVIEW Data types. Both VIs are polymorphic. You have to select the instance manually at the "Variant to Data" vi, because a Variant can be any type.

QUOTE(sara @ Jan 27 2008, 01:18 PM)

hi all

i need your help in my problem .

I read the date and the time of computer and put it in access table , but i need to read date only ..

help please

use the "format Date/Time String" primitive and display the date in a string control.

http://lavag.org/old_files/monthly_01_2008/post-885-1201502731.png' target="_blank">

Use Ctrl+H to see how to build the format string ....

QUOTE(CHRLAB47 @ Jan 24 2008, 11:46 PM)

Newbie question:

I’m controlling EXCEL by invoking a Method to Delete a Range of Cells..

What Data Type would be applied to the input of Shift?

Thank you, Chris

in doubt I'd take a look at the function description at the MSDN (http://msdn.microsoft.com). Hint: type e.g. _workbook.open into the search window and the Object definition should be among the first 10 search results.

Warning: if that input is a nested Variant, e.g. a string array, it is likely that you have no chance in LV to build that specific data type.

QUOTE(Kun @ Jan 24 2008, 10:52 PM)

Hi,

I have Ni-USB 6120. And Labview 8.5 Basic.

I am new to Labview and have read and made a pulse generating block diagram using the Pulse Generation Tutorial, but I want to do something and cant find it,

I want to generate pulses with a push button, i.e., when I push the button, a pulse of a preset frequency and duty cycle should start. Pressing the same button should stop it.

In the Pulse Generation Tutorial provided by NI, I dont see any where to put a button.

How would I go on doing this?

Also I asked on the NI Forums on how to change the line where the output pulse is going, but he just led me to some tutorial which I could not understand.

Can anyone help please, I need it done before Monday, thanks.

Please Help

Kun, you should take a look at the "event structure" tutorial in the example finder and at the "state machine" tutorial. You'll need that to solve your problem:

1. catch the "button pressed" event with the event structure

2. change the state of your state machine from "running" to "idle" when the event occurs ...

QUOTE(beckerg @ Oct 28 2007, 10:25 AM)

greetings from Munich

G. Becker

greetings to munic from an "exile bavarian*" in Duesseldorf

*but as long as I can get "Erdinger" here I can hold out

QUOTE(neB @ Jan 18 2008, 02:34 PM)

I passed the CLA re-cert!

and a couple of my rookies did the same. We now have 6 architects.

Ben

gratulations

is there any difference between the first certification exam and the recertification exam?

QUOTE(crelf @ Jan 11 2008, 11:11 PM)

CTSA is actually CTA = Certified TestStand Architect CPI = Certified Professional Instructor

Ah, thanks!

Nope CTA is definitvely not on my list. I don't even have Testatand installed. CPI is not on my list, too, because I have no ambition to lead courses.

QUOTE(Norm Kirchner @ Jan 11 2008, 05:25 PM)

Wow! I have to say that's the first time that I've heard crap and p4 in the same sentence other than "most other stuff I've used is crap but then I started using P4."

I've been using VSS for to long ...

(just my 2 cents ...)

QUOTE(Norm Kirchner @ Jan 11 2008, 08:58 PM)

... I never got that working ... (that's one of the reasons ...)

what the heck is CTSA and CPI?