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  1. Palletjack

    Led time large power transformer

    Just got a quote two months ago for a 25MVA. A little over a million and a quarter, with a 130 week lead time. Our last one was ~$650k+, but that was pre covid
  2. Palletjack

    About three-phase unbalance standard designed by electricity company

    3% is the norm
  3. Palletjack

    Step/touch potentials inside the ground grid Vs at the edges

    We only use pole ground mouldings on poles in certain areas of our system that is more prone to copper theft. Its like putting a lock on something, a dishonest man that steals will cut the lock. In our case, remove the moulding. Copper clad steel is a better deterrent. Harder to cut and has no...
  4. Palletjack

    Mixing reclosers on the same pole

    Three phase line. We have a fuse on A phase which feeds all customers where the line splits to the east to residences. a 70V4E on the B phase tap that goes about two miles before it has the first customer where it drops to single phase and feeds quite a few customers. We have a 35V4E on the C...
  5. Palletjack

    Ground Rod

    I assume you’re an electrical inspector? If so you should know the NEC. One rod, documentation of <25 ohms. Two rods, nothing required.
  6. Palletjack

    Unknown 115 kV component

    The second picture is taken from about 40’ away. Could be the distribution is just above the camera view… Theres also a distribution line in the picture running parallel with the transmission.
  7. Palletjack

    Unknown 115 kV component

    Have to agree with David here. In the first picture, is that a distribution line perpendicular and under the transmission line? I would want something to short out before transmission lines fell on distribution lines.
  8. Palletjack

    Utility Generator Export Issue(Imbalance)

    @energyfit…. I wasnt trying to be hateful, just letting you know another position. I work for a utility and we do NOTHING for anyone backfeeding to our facilities for free. We charge for everything they need or require. Its pretty much standard practice across utilities
  9. Palletjack

    Utility Generator Export Issue(Imbalance)

    Just a thought here.. You’re running this generator to backfeed to the utility and get paid for your production? What incentive does the utility have to correct an issue that affects only you? Offer to pay for the balancing and see if they are willing to do it then.
  10. Palletjack

    High voltage on utility transformer secondary

    Couple of things.. A 13.2 xf on a 13.8 system (or vice versa) would produce voltages at 230V or 250V. Not 270 or 280 Maybe a 13.2 Xf on a 14.4 system? That would make the voltages that high, but it wouldnt have went high all the sudden. It would have been high at installation and should have...
  11. Palletjack

    Capacitance on bushings of tr

    You guys install this bushing? Is there a lot of paint on the mounting flange of the transformer? As others have said, check your method and make sure your grounded.
  12. Palletjack

    transformer highest temperature attained temperature indicator mysteriously spikes twice

    Most winding temperature gauges are out of calibration. I wouldn't trust it as there are too many variables at play. Tap position, loading, calibration, etc… When is the last time the oil temp guage has been tested and calibrated? There really isn’t a way that i know of to test or calibrate a...
  13. Palletjack

    Generator 400v output to 11kv step up transformer - need vector group confirmation

    Understand also you can inadvertently change the vector group by wiring the generator outputs to the secondary side of the step up transformer simply by connecting it with the wrong rotation. so connecting it ABC X1,X2,X3 will be YNd11, connecting it ACB X1, X2, X3 will result in YNd1
  14. Palletjack

    How to convert 12 wire generator to single phase

    Thats a 4 lead generator according to the plate. You positive its 12 lead? Have you looked at the connections?
  15. Palletjack

    Pole mounted distribution transformer neutral connection

    They should all be interconnected. Connect the pole ground with the neutral wire on the pole, and run a tail from the mainline neutral through the neutral bushing in the transformer.
  16. Palletjack

    North Carolina power substations taken out by gunfire

    We rolled some waiting on solar to ramp up and carry extra burden. Done around 9:30AM.
  17. Palletjack

    Substations vandalized

    That sounds good, but then how do you protect the miles of line with insulators at each pole? You make transformers bulletproof, then they start shooting interrupters, bushings, regulators, reclosers, breakers.. the list goes on and on. Question is.. how high you want your energy costs for...
  18. Palletjack

    North Carolina power substations taken out by gunfire

    There was another attack on a North Carolina power distribution station three weeks prior to this latest incident: Another North Carolina power substation was disabled before the Moore County attack https://www.newsobserver.com/news/local/article269...] Yes. But that area had an extensive...
  19. Palletjack

    Determining substation equipment life expectancy

    We recently retired a station transformer. It was 1943 model. Breaker and regulator changes, with good maintenance on switchgear, motor operators, and interrupters should last well beyond 30 years.
  20. Palletjack

    Outage on distribution circuits due to high humidity

    What types of pollutants are in the area? “Very humid” conditions only shouldn’t blow fuses. They don’t blow when it rains I’m assuming? The rain washes the pollutants away.

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