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  1. HamburgerHelper

    ETAP and SKM: Bus count for packages

    I am looking at packages SKM and ETAP packages. They have you buy in at various maximum bus counts for a project. SKM has 50,100,300,1000,2000,5000, and 12,000. I am thinking both of them try to sucker you in into buying too much. What is the bus count you have found at large facility? They...
  2. HamburgerHelper

    Non-Profit Engineering Firm

    Has anyone heard of a non-profit engineering firm? In a very brief look, I saw that their are provisions for scientific organizations. I imagine that you could pay employees more if you had this designation by avoiding taxes...
  3. HamburgerHelper

    Generator Underexcitation Relaying

    How bad is it to have 40 elements with 0.5-0.6 second tripping times for large units? How quickly does tripping need to happen during an under excitation event to avoid damaging the unit? ------------------------------------------------------------------------------------------ If you can't...
  4. HamburgerHelper

    Distributed single phase generation

    How do utilities handle a bunch of distibuted single phase generation feeding back onto the grid? Is it managable? What problems does it cause? ------------------------------------------------------------------------------------------ If you can't explain it to a six year old, you don't...
  5. HamburgerHelper

    PRC-005 Relay Monitoring

    Does anyone have any issues with getting the NERC PRC-005 maintenance 12 year window with having maintenance staff checking the relays periodically, like nightly. We don't have the relays connected to SCADA but someone should be regularly doing the rounds to check for equipment that has...
  6. HamburgerHelper

    Out of step blocking or tripping

    Can out of step blocking or tripping be set confidently for generation without a transient study?
  7. HamburgerHelper

    Generator operating frequencies.

    I have thought about this for awhile and I don't understand it. So, let's say you have generation spread out over a large region and there is a disturbance in the system that causes one of the generators to be at a lower or high frequency than the rest of the generators in the system and the...
  8. HamburgerHelper

    Transmission line length changes

    How much does the physical length of a transmission line change with temperature and physical loading?
  9. HamburgerHelper

    Switch from ground overcurrent to ground distance

    For transmission, has anyone completely replaced their ground overcurrent schemes with ground distance protection. How difficult was it? Were there extra studies needed? What scenarios were looked at to validate the settings so they didn't underreach or overreach due to mutual coupling or...
  10. HamburgerHelper

    Residential: Aluminium wiring

    I looking at maybe buying a house that was built in the early 60s and it has aluminium wiring. The disclosure form makes mention that something was done with connectors. I think this is for the connection by the outlets but I don't know for sure. How much of a red flag is this? I am not...
  11. HamburgerHelper

    Phase distance relay overreach

    Am I thinking about this correctly? If you have an arrangement with a delta-wye-grounded transformer feeding a plant and a line to ground fault happens on the low side, the phase distance relaying on the high side can overreach to the low side due to load current on the other two phases...
  12. HamburgerHelper

    Reclosing into unsynched generation

    How is this usually handled? We have a situation were a breaker reclosed into a line that tripped out on a temporary fault. There was tapped generation on the line. The generator supported the voltage on the line but it was below the dead line voltage and the relay reclosed into the generator...
  13. HamburgerHelper

    Naming a consulting company

    What are the stipulation on naming a company in the U.S. if there is a company in Singapore or India that has the same or very similar name? Does this cause issues? I don't think they do work in the U.S. if that means anything.
  14. HamburgerHelper

    Open phase detection on distribution

    Our system has an issue with detecting an open phase or an open phase with a jumper that swings down into the phase below it in our distribution system. The arrangement is a step down delta-wye grounded transformer in the substation that feeds a bunch of wye-ground-wye-ground distribution...
  15. HamburgerHelper

    Two bundles one tower

    I have a tower with two bundles that are on the same circuit. The problem that I am running into is that the relaying under reaches for a fault on one bundle due to the parallel flow on the other bundle. This has to be a problem that has been solved a long time ago. Do you usually just put...
  16. HamburgerHelper

    Tire Engineers

    I thought this was a laugh but a tire shop here, "Tire Engineers", in Houston,TX got fined $5,000 by the Texas Board of Engineers. Tire Engineers; Case Number B–35363 Violation: From on or about June 17, 2014, and continuing to the present day, Tire Engineers operated stores located at 3801 FM...
  17. HamburgerHelper

    Fault current ground path

    How come I never see the impedance of the earth in fault current calculations? If you have a fault, doesn't it have to makes its way in the ground back to your ground source or sources? I see stuff associated with creating a low effective fault paths in the NEC but nothing elsewhere for...
  18. HamburgerHelper

    Faults producing radiowaves

    This is kind of a goofy question but is there any reason why I shouldn't be able to hear faults on the transmission system using something like a radio. Lightning strikes are about the same magnitude of current as a good ground fault on our system and I can hear lightning strike on AM.
  19. HamburgerHelper

    Ph.D in power engineering

    I see a few people in industry that have Ph.D and work in substation design and protection in my region. I don't know if they need it for anything or how much it helps them with clients? Does a Ph.D in power engineering open any doors that a MS doesn't? What kinds of things does it let you get...
  20. HamburgerHelper

    Gapped core CTs

    I see that there are manufactures that make gapped core Cts. Does anyone actually use these to help mitigate CT saturation during transformer inrush or other DC offset issues?

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