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  1. bertisevil

    Delta on a Wye system

    Thanks for all your replies. If this was a new station service, it would be a Gnd Y - Gnd Y and I would not have any concerns. B
  2. bertisevil

    Delta on a Wye system

    Actually, now that I think about it.... in the closed and open delta banks you can get the 208 volt from the other legs to ground. My bad. Wasn't planning on using it that way but it is there. B
  3. bertisevil

    Delta on a Wye system

    This is a closed delta 240 padmount with a center tap on the third leg. Gives 120/240 on that leg. Open delta would give you a 208 leg. Bob
  4. bertisevil

    Delta on a Wye system

    DPC, You are correct, distribution feeder. Waross, Almost correct, the secondaries will yield 120 ph-gd and 240 ph-ph on the leg with the center tap grounded. I am mostly concerned with primary side issues. Thanks for the feedback, guys. Bob
  5. bertisevil

    Delta on a Wye system

    What are the ramifications of connecting a delta transformer to a grounded wye system? Available primary is 12,470 GrdY/7200. The 3 phase padmount is 12,470 delta. Secondary is 120/240 delta with one grounded leg. The voltages are correct and the transformer will work. I am concerned about...
  6. bertisevil

    2009 NFPA 70E / Impact to Utility

    Not necessarily so, wbd. OSHA may not have jurisdiction over that utility and thus would not have any power to site anyone. Depending on the area of work (see stevenal's thread), NFPA or NESC may or may not apply. Depending on the laws (state or local governments may or may not adopt the...
  7. bertisevil

    Cleaning EPR

    Avoid anything with 1,1,1, Trichloroethane in it. The industry got away from this stuff years ago. The Raychem kits contain Polywater's cleaners. So either company's kits will do. Most importantly, wipe from the concuctor back to the semicon, not the other way. These cleaners will track the...
  8. bertisevil

    American mains voltages

    My guess is that it won't. As the blacksmith answered the voltages are nominal. Depending on where you are your voltage could be 110, 115, or 120. My nominal service voltage is 120. If they changed the rating on equipment to 110 or 115, I probably would not be able to use it. I would suspect...
  9. bertisevil

    Shielded Cable versus Concentric Neutral??

    Correct me if my calculation is wrong for the amount off neutral. The cable is 1000 mcm Al 15kv 100% LC shield. This would give me a diameter of about 5.12" at the shield. 5.12 = 5120 mils. 5120 x 8 mils x 3 phases = 122,899 sq mils. 122,899 sq mils/0.7854 = 156,480 cir mils. 2/0 =...
  10. bertisevil

    Shielded Cable versus Concentric Neutral??

    Let me correct my first post as I had done some quick calculating and then got interrupted. The shield is equivalent to somewhere between a 2/0 and 3/0 Cu Oops. Bit of a difference, but still way below the rating of a CN. This is adequate under the right conditions to functions as a neutral...
  11. bertisevil

    Shielded Cable versus Concentric Neutral??

    Stevenal, my system is in plastic duct. So, if appears to me that all of section 35 will not apply as it is called "Direct-Buried Cable". Correct? Section 96 is very general and does have some bearing, I'll agree. I am continuing to search the NESC for more. jghrist, you are on...
  12. bertisevil

    Shielded Cable versus Concentric Neutral??

    Thanks gordonl, I apologize. I should have stated the the system that I am referring to is a grounded Y 12470/7200. It would be a waste of money to buy CN cable for a delta feeder.
  13. bertisevil

    Shielded Cable versus Concentric Neutral??

    I have run into a situation where a utility had decided some time ago, for whatever reason, to replace there main feeder cables with shielded EPR when they need to be upgraded. Their old standard was concentric neutral cable. For example, a feeder getaway would be upgraded from 750 Al 15kv...
  14. bertisevil

    3-ph, 21kV grd Wye-Wye Transformers Connections

    You are both partially correct. The manager says, 3 phases, that is correct. You say 4 wires, that is correct, also. The primary you stated is a 2 conductor cable. By pulling in 3 phases you, in reality are pulling in 3 phase conductors and 3 neutrals. The concentric neutrals on the pole...

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