musicguy1800, no offense was intended; I appologize if it sounded like that. It is only that you had a correct intuition (from my point of view).
To Aferguson: I think your actual question is: "What is wrong with my equations when I consider the voltage taps?".
Indeed, performing the...
Sorry for this late post, but I have had a long time reading and studying the info and formulae given by various members and trying to match them with the shc theory that I know (which I have learned at school). I come from a diferent school which sometimes (manytimes) has different approaches...
I agree to jghrist. The voltage drops do not affect directly the shc current value.
Basically and very much simplifying, the short-circuit reduces to a circuit formed by an equivalent impedance connected to the source (it is a "short" circuit). The shc current is basically I=U/z. The...
To Voo:
1. A star to your post. Real thanks for info given upon the Icu and Ics currents. I knew the test sequences of each current (qualitative conditions) and the capability of CB to carry, resp. not to carry its rated current (quantitative conditions), but I couldn't understood the physical...
Hi uno.
A. Please forget my first message.
B. Sorry for this delayed response. My attempt to understand the differences between the three currents took me more than 1-2 days that I expected. I have been checking for and thinking to the three currents over and over again. I have come to some...
Please excusse my English. Can you re-phrase the sentence "which in turn determine the short-circuit rating of the switchgear for 1sec/3sec (i.e. 40kA for 1 second)"? I don't understand. Thank you.
For Icw (selection of CB based on the shc current value at time 1 second): No. The...
Thank you for your replies. I still have reserves for "wutz" (due to German influence - it would have been very easy to be used "what's"), but I am happy the matter has been solved out.
Sorry for inadvertence.
busbar, what "FWIW" does mean?
electricpete, what "Wutz" does mean? Is your irony strictly limited to my English or is extended over my person too?
To the rest of the members: thank you all replying to my question. I have got the answer I have been looking for.
I responded to a question of this forum (cable selection based on duty cycle) where I afirmed that the r.m.s. value is similar to the thermal equivalent current. I realized this may be a stupidity (in fact, I am pretty sure).
I analyzed the problem and now I believe that the r.m.s. value of a...
Thank you, jbartos. I am not an American teritorial and I cannot get the book you referenced, but thank you anyway.
I have been thinking to the problem and the result is that I realized I made a mistake, resp. it is obviously that the torque is direct proportional with the load (I2 current); I...
The question is refered to a 1P synchronous generator. It is known the output voltage U2, nominal power, revolution rpm, synchronous reactance Xs and pf of load (e.g 0.9 inductive). The rest of parameters are neglected/neglegible.
1. How can be determined the nominal internal angle teta, the...
Hi syssafety,
It does not appear from your message if there is about a 3P (three-phase) or 1P (one-phase) system, and AC or DC system. This has impact on the number of conductors of the supply (feeding) cable, resp. 3 or 4 conductors for 3P systems (3 conductors for the 3 phases and 1 conductor...
