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Szar

Supporting Member
  • Content Count

    347
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160 Excellent

About Szar

  • Rank
    Commander of the Legion of the Unholy Pear

Profile Information

  • Gender
    Male
  • Location
    Somewhere over the Rainbow

Previous Fields

  • Engineering Field
    Left, Occasionally Right, Sometimes Middle.
  • License
    EIT
  • Calculator
    TI
  • Discipline
    Electrical

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  1. Szar

    Oct 18 PE Exam

    So us April-ineans set the test score for ya. Sucka's!!!!
  2. Szar

    NEC motor protection help

    An engineer will never ever use that section. ("Never" is a dangerous word, but I'm comfortable saying that here.) "is not sufficient to start the motor or to carry the load" The only way you jump into this section is if you designed to (A)(1) and (B)(1) and the motor still failed to run properly. Repeatably. And the overload itself was the problem... which is usually never the case when sized appropriately. At this point in the diagnosing, is a field technician's / electrician's domain who is doing the commissioning and startup and cursing the engineer for their "shitty" drawings. (Unless you do commissioning too, then your blaming the designer who obviously messed up your intent.) As a test problem it would basically have to be stated that the overload was sized according to 430.32(A)(1) and (B)(2) and still failed to run. Very important and self evident information in the problem that almost answers itself for you, and unlikely to be a test problem.
  3. Szar

    Oct 18 PE Exam

    Lies. Civil engineer's don't even need to count past 9 to do their job. Do they even know how to multiply?
  4. Szar

    RESULTS!!!

    Just do not try a Manager or PM. You'd need like 6 Managers or 4 PMs to get an equivalent exchange there.
  5. Szar

    Oct 18 PE Exam

    Anyone else hear about the NCEES warehouse fire that burned up all the scan-trons and invalidated the last test?
  6. Szar

    NEC motor protection help

    What part of the code are you following here?
  7. Szar

    NEC motor protection help

    This in particular tells me you may not be familiar with Motors. So... an overload IS NOT a breaker or fuse (normally). Its an entirely different class of device, completely separate from the breaker that acts as a short circuit protection device in this case. In the rest of the code, the breaker / fuse serves as both Overload and Short circuit protection. With motors, that is broken down into separate devices. The breaker you are familiar with only protects the cable against short circuit, and is sized according (typically much larger then would otherwise be a allowed for a load.). The overload (while this type I will describe isnt commonly used anymore) is called a bi-metallic overload basically a spinning gear that when is heated causes a material holding the gear in place to melt and the gear to turn. When the overload is in its melty state, the circuit can be broken by the gear and requires either an automatic or a manual reset depending on what you ordered and its configuration. (Now adays solid state overloads are the bees knees.) Overloads come in sizes down to fractional amps up to hundres of amps. Whereas standard OCP breaker / fuse is only common whole numbers and you usually dont see any below 15Amps for breakers but fuses can be fractional amps. On really small motors, the breaker is permitted to be the Short Circuit and Overload protection... but that is again moving outside your question. edits in italics
  8. Szar

    NEC motor protection help

    So first things first. Motor Short Circuit MUST BE sized based on NEC FLA tables in 430.Motor Overload MUST be sized off Motor Nameplate. Not the FLA given in 430 tables. This is dictated by NEC 430.6(1) and (2). You can get into circumstances where Short Circuit and Overload do not match due to the range of values permissible by different base numbers and different multiplies. How the values you provided relate to 430 Part XIV tables and nameplate... not sure. But if the question has those terms, you need to use them. You also miss important information like OCP type for the Short circuit protection, confirmation its a separate or integral overload, how its started, etc etc. Cable seems correct. Short Circuit seems correct assuming the 250% is because you have a I2t Breaker (inverse time) and not an MCP (instantaneous trip) which tends to be much more common in today motor starter world. Overload is one or the other. Its not a range. Usually its 115% of Nameplate as that encompasses 99% of most usual cases... however not enough information to confirm which number you should be using. I've been up since 2 AM with a screaming child though... someone should double check me here.
  9. Szar

    Oct 18 PE Exam

    Clearly the test needs to be harder based on a few individuals I've had the honor of coming across in my career!
  10. Szar

    Oct 18 PE Exam

    But if your XOR ASCII checksum of the email date and time results in a prime number, you can file a TPS Report with NCEES and protest your failing score. My Sister's ex boyfriend's boss passed that way.
  11. Szar

    Oct 18 PE Exam

    You may just need to find friends who are better at passing tests.
  12. Szar

    Oct 18 PE Exam

    Your name is not Baconator. You do not pass go. You drift slowly into the dark realms of ambiguity, this post forgotten and discarded like a politician's pre-election promise, never to be uttered again in light of day.
  13. Szar

    NESC, NFPA 70E, 497, 499 & 30B

    Which is what I did. I got work to split the cost 50/50 mostly. All said and done, the specific resources indicated by some of the others are generally your safest bet... all things considered. Your abuse may vary based on the test given though.
  14. Szar

    Protection Problems

    Morning Session I did not struggle. Afternoon Session I would have liked another 30 minutes. Questions were typical of the NCEES exam. Generally. But there were a few questions that if you told me I could call anybody during the test to ask them for the answer, I wouldn't even know who to call to get an answer. Hell, if NCEES gave me the Author of the question I'm not sure I could have phrased a coherent question about their question! (Edit... Other then "WTF is this garbage!") As for the Theory vs Numerical... cant answer that. Part because I don't remember, part because I'm not sure we can?
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