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  1. erdep

    ERDEENG (erdep) software/modules

    I send a sample file now. Regards Note: there is a free "professional" software better than rho32: search for ipi2win. https://files.engineering.com/getfile.aspx?folder=e018e41f-5cea-4930-a5ac-6a9801237a0c&file=rho32.dat
  2. erdep

    ERDEENG (erdep) software/modules

    WhyEMC: Try https://www.dropbox.com/scl/fi/s6ti5siczplgilxfbwp0b/erdeg64eng.zip?rlkey=tc1tfr6vit9onm8n1360u9xya&dl=0 Regards.
  3. erdep

    Earth mat design Using ETAP software for Industrial substation (High Short current Fault)

    Saiedsadat, I am not sure if the Standards have such probability coefficients. More transformers, more fault current, but current to ground are no increased, because the bigger fraction of current returns via neutral to the transformers. In some cases the neutrals of transformers can be...
  4. erdep

    Earth mat design Using ETAP software for Industrial substation (High Short current Fault)

    Saiedsadat, In low voltage circuit, the current to ground can't be bigger than Uphase/Rground, or Uline/sqrt(3)/Rground. I assumed that your Uphase was 0.217 kV as the figure you sent, really is is 0.400/sqrt(3)= 231 V. Rground is the resistance to ground of your grid1 electrode. The SC...
  5. erdep

    Earth mat design Using ETAP software for Industrial substation (High Short current Fault)

    Saiedsadat, The 75 kA may be correct as fault to metallic circuit, but the current injected to ground cannot be bigger than 0.217/Rground, surely a small fraction of 75 kA. Regards,
  6. erdep

    Viewing magnitudes from COMTRADE files

    Gtpplot reads the .cfg file and uses timemul I your example, timemul is 0.477225214242935 It is in micro seconds The .dat contains: 1,0,267801390,1676682854,-1947471288,84259708,482838889,-574376845 2,349,401917008,1593459685,-1998414489,111587178,464445025,-587236013...
  7. erdep

    Viewing magnitudes from COMTRADE files

    Bacon4life, I am developing Gtpplot as an EMTP-ATP viewer. The program can read COMTRADE files, but I have not access to true COMTRADE files, I am retired since 1996. Any example of such file are welcome, I can correct the reader using it as a reference. The signal has harmonics that are not...
  8. erdep

    Viewing magnitudes from COMTRADE files

    Bacon4life, Can you send the files (.dat and .cfg) of your case? I want to try it with gtpplot. Thank you
  9. erdep

    Atpdraw motor start (Motdatpr)

    LuizRocha: It is a link to my dropbox account: https://www.dropbox.com/s/8roza6j0inh1o1w/motdatpr.zip?dl=0
  10. erdep

    EN 50522 permissible touch voltage - body resistance question

    Tofulover, A bit better. The problem with the standard is that the tables are coarse, any deviation from the exact R(V) or I(t) multiply the errors. If you try with RF > 0 (using the graphic method) the errors are bigger. It is a case where one must have faith... and I have not faith in the...
  11. erdep

    EN 50522 permissible touch voltage - body resistance question

    Tofulover, You calculated the third column of your table (Ibody) applying the BF factor 1000/775= 1290 mA but you have 1719 mA (1290/0.75) Are you using the third column to calculate Utp? If yes, you calculate Utp using 1/0.75 times de current. Regards, OPH. 2020-06-22 09:53
  12. erdep

    EN 50522 permissible touch voltage - body resistance question

    Tofulover, You obtained a table of I(V) and R(I) with exact values for the table values, and a good approximation for the rest of values. Now, you can use a table of I(t) (or t(I)) to calculate V(t), as the EN50522, with the HF, BF and Weight for each case. The last step is to compare your...
  13. erdep

    EN 50522 permissible touch voltage - body resistance question

    Tofulover The paper shows how to solve the non-linear circuit graphically. The tables are from a old Standard, I obtained the coefficients for R(V) 50% with the table if EN50522: There are a lot of linear (as Excel use in your figure) and non-linear fitters. Vtouch Table EN50522...
  14. erdep

    EN 50522 permissible touch voltage - body resistance question

    Tofulover To be sure about the problem of lin-lin itnetrpolation I was clear, I prepared two figures. A table of ten values of x (1...10), y=10/x. In both cases the interpolation was done linearly, from x=1 to 10 in 0.1 steps, but the second figure was calculated with the procedure x-->...
  15. erdep

    EN 50522 permissible touch voltage - body resistance question

    Tofulover When you have not a function to calculate a value from some argument, and you have a table, you can interpolate using the table. If you have few values in the table, the linear interpolation may work well for some cases, but if yoy want a log-log plot, you will see not rectilinear...
  16. erdep

    EN 50522 permissible touch voltage - body resistance question

    All the Standards define Current as the variable that can produce risk, and finally all define tables or curves of Voltage. Look the Current(time) for different Standards (or author in one case), some obsolete. Depending of how the Standard define Rbody the calculation will be easy (IEEE 80...
  17. erdep

    EN 50522 permissible touch voltage - body resistance question

    Tofulover Your procedure solves the problem for one of the four circuits each time. BF is a factor to modify Rbody to take into account the real circuit HF is a factor to take into account the true current by the heart Look Annex A of EN50522 Vt - Zt(HtoH)- Zt (HtoF)- Ib 25V - 3250 ohm -...
  18. erdep

    EN 50522 permissible touch voltage - body resistance question

    Tofulover Yes, it is correct. To complete the work you must calculate four tables as you did, with the corresponding HF and BF, and calculate the weighted average to obtain the table B.3 (or the curve of figure 4). The curves of figure B.2 require the addition of RF for each case. You end...
  19. erdep

    EN 50522 permissible touch voltage - body resistance question

    Tofulover, The link to the Fortran code: https://www.dropbox.com/s/1h57g7hitc8eiwj/touchall.f?dl=0 It can be compiled with Mingw32, Gfortran or Intel compilers. Regards, OPH. 2020-06-19 16:28
  20. erdep

    EN 50522 permissible touch voltage - body resistance question

    Tofulover No, it is not a simple job to do it manually. The simplest method is the bisection: Link But in this case you have not a closed function to calculate. You have one (or more) tables with few values. You must found a value in a table, and the best is to use interpolation. But...

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