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335_x

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About 335_x

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    Veracruz, México

LabVIEW Information

  • Version
    LabVIEW 8.6
  • Since
    2007
  1. ok... they gave me permission to ask properly.... I have .xls sheets... (I hope I wrote it right) they were written from a signal they measure a while ago, they do not have the conditions to measure those signals again, but still they want to use the information in that files… So the conditions of these signals are actually weird, they change a lot in their amplitude and frequencies… but It was told to me that I consider converting a single period of a signal into an amplitude Vs Degrees instead of an Amplitud vs Time graphic, so the first thing I have to do, is to get the values from the .xls file, I did it into a 1D- Array, and now I want to measure how many values make a complete period, this is comparing the value of the array with the previous one, if there is a sign change.. well actually a couple of those, I have to cut the array, see the size of the sub array, divide the number of elements by 360, and append to each value the result of the division times 360, you know, to relate each value of the array with the angular value of the period of the wave it represent… I know… sounds like it could be easier done but…it is not my idea, I’m just following orders… Anyway… if it is something that people do… ¬¬ well if it is actually useful I thought that may one of you have done it before… Thanks a lot anyway, and have an ice day…
  2. this is what i've done.... i cannot upload the .xls file it is reading... so what's the diference anyway... convertir angulos prototipo.vi
  3. Greetings… i salute you… or something like that I need to do a very specific task in LabVIEW this week… and I kind of have some ideas to do it, but i have to use a lot of imagination to do this... the fact is that i remember a numeric method may be programed with the shift registers in a for or a while looop structure, by making the register grow down... (sounds wierd but i'm sure you understand what i mean)... this works or at lest i've used it before, when we are just generating the values that are getting inside the shift register... but what if i have already an Array with the whole values i need to use, any ideas about how may i compare the values in orther to slice the array when there is a couple of sign changes??? i'll keep trying, and i know is verry basic... but when you are " " you may not see the obvious answer... thanks..
  4. No WAY!!!! I always thought that if I make an average of a Sine Wave.. I would get Zero… or something as close as zero as possible…. Gb119, I apologize because I actually thought that you were Crazy at first but it actually works… and works perfectly… This method is awesome… I wonder what’s the math behind this… are you guys warlocks or something??? Is it witchery??? I keep searching about it with the name “phase-locking” and the other names Black pearl gave me, and I found that is usually done in Labview.. they use the Hilbert Transformation to make the sine wave a Cosine wave.... well kind of... and then use the statisitic average and to the inverse of the Tangent they use the complex Numbers convertions.... So this is what finally was done i just don't know what is the "x 2" for... and at first i use the "Normalize Waveform" to see if the filter response is something not to care about... well i'm between afraid and impressed, i actually learn something new tanks a lot guys...
  5. Ok, first of all i want to say that is my pleassure to have this trouble and to have to fix it my self, so i don't want to sound like those students that actually want their homeworks done... it is just that perhaps i need another point of view ... So here is the deal, i have a 3-phasic electric system, of currents, the currents came out from a filter so, ignoring the response of the filter, i have to meassure the phase angles between them... i know there are downloadable modules to do this, but the fact is that the time they use to meassure things like RMS values or else... it is a trouble cuz i have this response in my signal well... let's pretend that i save my signals, the 3 of them, in .xls, and that i am going to errase somehow the non-stable part of them, just to keep the stable part of my signals, eventhough the "sub vi's" like "EPM_Phasor.vi" or "EPM_Phasor diagram"... i kind of bielieve that they are telling me lies... because they are triyin to meassure angles of current or voltage of the same phase, so those are never going to be more than 90°, but , in my sistem i may have 120° of separation between phases... so i did this two things: the first i tried... to use some trigonometrics with the RMS value of my signals, and then make a subbstraction of the signals, and take the RMS value of that too... in order to have a triangle, wich sides i know... whit Cosin Law, i'm able to see the angle, how do i know if the angle is positive or negative???, how do i know if i'm getting the supplementary or complementary angle or if i'm gettin the actual???? i finaly have the angles.... but i don't know if they are positive or negative... my second try.... i used the RMS value and the DC value to calcule as if it was Power Factor the angle between the two currents... i have the same trouble because power factor is "Cos" if that angle... anyway... that's my case... sorry about my bad use of english... but i'm mexican, and even if i try i do not, i repeat, i do not speak english... so greetings.. angulo para armonicas.vi
  6. Does someone could make me a vi with a single polar display (by polar i mean complex number) i've seen before but i do not have the power meassurment toolkit or i don't know wich toolkit it is ... but i've also seen before that i can open copy and paste in another .vi, ... and please let that be labview 8.6... i'm in a hurry!!!!! thanks
  7. well... everyone deserves to be free... and it's kind of wird... but, i didn't find another way to translate a PLC logic to this stuff... i actually use more local variables at the end... let me show you... animacion tanques cisterna 3.vi
  8. ok, i'd been working my ass brain out since like 2 weeks ago to build this .VI.... and... welll.... i don't like it...:( do you know where can i find nicer pictures ... (even if they are not made by me) ... to build this kind of animation... i used corel Draw... but that's suposed to be a pump... and it seems like an "escafandra" animacion tanques cisterna.vi
  9. oh.. thats awesome... by the way.... I No Speak Americano.... (neither italian) what's a cuddle???
  10. ok.... thanks... to the bee and thanks to the devil... where can i get some Labview classes.... my current teacher is evil, i mean... there was no need to make us do that just cuz' we wer sleeping in class... by the way... i need to solve a numeric method... and find some %error... but as i sayed... that's my work...
  11. i remember that a while ago there was something written under the nickname that use to say "i'm a LAVA, not a Fighter"... as long as all you people let me ... i'll try to believe that... Well... this time is something kind of simple... i need to calcule... well... thats my job... but the thing is that i need to keep the last 3 values from a shift register... to keep the last two is as easy as get the value as it comes out from the shift register and then get the value after the operations i do with it... befor the value enters again in the upsidedown triangle... i could just use a for loop... and i would get an array with all the values i need... but you know... when you are in school, you kind of have no freedom... well thank you anyway....
  12. sooo... it's kind of a sin to do this in an excercise as simple as this one... circuito prueba 1.vi
  13. i feel so ashamed of my logic right now... (in math, a circle is the constant function in polar coordinates) perhaps in a polar graph... this cuold be even easier... anyway.... thaks to all of you... i'll finally keep this one for future references... circulo.vi
  14. so i have build simulations about damping systems in labview just for fun... but now that i'm taking a signature wich needs me to use it i can't find what i'm doing wrong... this is a trouble with a circle... i just have to draw it, i was thinking about using the formula node and the circle ecuation with se center in the origin... but some how this does not work... have you ever draw a function you already know in a Graph XY with arrays for the X and the Y values... Untitled 1.vi
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