Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations MintJulep on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. Okpower

    Venezuela´s general blackout

    There are 2 main public explanations or theories: 1. Virus infecting the control system or hacking, EMP attack on transmission lines (!!??), and physical attack on main transformers similar to sabotage on Sillicon Valley substation...
  2. Okpower

    Venezuela´s general blackout

    Hello everyone: How credible is that a general blackout could be caused by a virus infecting the control system of a hidrogeneration plant with 20 electric generators? And what about electromagnetic weapons disturbing electric transmission lines? Is that possible? Regards
  3. Okpower

    Automatic Transformer Tap Changer connected to 20 MVA Turbogenerator. Stability

    In fact, there will be two 20 MVA generators in parallel, feeding a 15 MV Petrochemical plant, and exporting the rest of the power to an 115 kV infinite bus. By now, I guess that I will apply the principle "Less is more". From your answers, an automatic OLTC may complicate the stability, and...
  4. Okpower

    Automatic Transformer Tap Changer connected to 20 MVA Turbogenerator. Stability

    Dear All: I am considering to connect a 13.8/115 kV transformer to a 20 MVA Gas Turbogenerator (13.8 kV). The turbogenerator has an automatic system to regulate the reactive and active power. The questions are: 1.- Do I have to use an automatic transformer tap changer to regulate the voltage...
  5. Okpower

    40 MW XFR vs 20 MW Turbogenerator

    Thanks for your answers. Actually, I could use a good approach, for just initial investment (cost of the XFR and the TG) e.g , "the option 1 could be 200% the option 2" or "the 20MW turbogenerator cost the same than a 40 MW XFR". Jghrist, the 40 MW XFR could be installed to have future power...
  6. Okpower

    40 MW XFR vs 20 MW Turbogenerator

    Hi all: I have to do a presentation for the management team about a comparison between two options for a petrochemical plant electrical feeding: 1.- To buy and to install a 40 MW, 34.5/13.8 KV XFR with its correspondent 34.5 KV transmission line (3 Kms), to feed the main substation. 2.- To...
  7. Okpower

    AWG vs. mm2 Cables procurement

    Hi all: I am involved in the procurement of about 20.000 meters of cables to be installed in a new Oil refining Plant. The contractor that is doing the design of electric system advised us to specify the size of cables in mm2, because there are more cable suppliers that handle this unit. At...
  8. Okpower

    Cathodic protection for copper grounding grid.

    MJCronin: As Electrical Leader, I do think this is a serious issue to handle. I would prefer to have ground voltage just 0 Volts, not 10 or 15 volts (that would be the voltage that cathodic protection could put in grounding elements). In any case, which are the solutions or the alternatives...
  9. Okpower

    Cathodic protection for copper grounding grid.

    Hi all: I work in the design of a new gas plant. Yesterday in a technical seminar, my boss proposed me to protect the grounding grid of the new plant with cathodic protection. I think it is unuseful, and not common practice. But I want to know your opinions in case that the proposal becomes in...
  10. Okpower

    13.8Kv Breakers Currents Rating

    Hi all: I am looking for information about the main comercial current ratings of vacuum breakers for 13.8 KV (prices will be excellent too). I need to feed eight areas (3 to 6 MVA each) of a plant in 13.8 KV, but i dont want to use 1200 A breakers, that seems to be the most common rating, but...
  11. Okpower

    Variable Flow Pump system with VFD

    This is a new project, for a new plant. And actually, it is difficult propose a 460 V motor for that power, because, the motor shal be capable to start with direct voltage.I have read about some "new" arrangement to control flow with several breakers, a small control logic and just 1 VFD to...
  12. Okpower

    Variable Flow Pump system with VFD

    Thanks itsmoked: Just to clarify, I am thinking in just 1 VFD..(1 pump will be driven by just 1 VFD)900 HP, 675KW. The second one will be operated directly to line, and the third one will be just in spare.
  13. Okpower

    Variable Flow Pump system with VFD

    Hi all: I am involved as electrical engineer in the designing of pump system for loading refrigerated products (PROPANE, BUTANE) to ships. This system will have a wide range of flow quantity since will be many different ships with many different capacities and flow rate limits. I am proposing a...
  14. Okpower

    Power Quality Meter Location

    Hi all: I have 2 questions for a new oil plant electrical system design, about Power Quality Meters: .- How valuable is to install a permanent Power quality meter in the new plant? .- Where should this device be installed (Control rooms, main substations??) I found some tips from the web...
  15. Okpower

    34.5 KV Breaker, Outdoor or Indoor??

    Hi all: I am doing a design for a 13.8 KV Substation. There are six incoming lines in 13.8 KV. Two of those incoming lines will come from 34.5/13.8 KV XRF's. Besides there are 20 outgoing lines in 13.8 KV. I want some suggestion about what kind of 34.5 KV breaker i should use: outdoor...
  16. Okpower

    3 mts High Elevated Substation

    Actually, the designer's reasons is "to give more cooling space for the cables" (3 meters high?!). But the maximun yearly temperature in the zone is 36 Centigrades. Our Civil engineer says that flooding is not a problem...the substation will be in an elevated zone, and they can make a good...
  17. Okpower

    3 mts High Elevated Substation

    Hi to all! I have just received the drafts of a 3 meters high elevated substation. The details include a space from level 0 to +3meters where the cables will be run and with the bottom entrance to the switchgear. Also, the drafts show the switchgear room 3 meters high with the respective...
  18. Okpower

    5MW XFR on 115KV

    My comments and conclusions after i read your comments: dpc, Zogzog, slavag: I have to find prices of 115 KV equipment (is very close to the Plant, 300 mts). And I have to evaluate the construction of a 13.8 KV, 5 Kms line to the Plant. But really, i think the 115 KV is the expensive option...
  19. Okpower

    5MW XFR on 115KV

    Hi, All: I am getting involved in a new project, for a Gas Processing Plant. The entire Plant needs 4,7 MW to operate, and according the visualization studies, this power will be supplied by two 115/13.8 KV transformers in redundant double bar (two 115 KV incoming lines). My questions: 1.- Is...
  20. Okpower

    Generator dissipation resistance.

    ...the process i was asking was the one answered by Sberbece...thanks

Part and Inventory Search

Back
Top