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Recent content by Bill West

  1. Bill West

    Why does my post keep getting deleted?

    I could see that if it had been moved to hobbies or if a request to continue there was made but this is more like glitch as the work the participants put into it has been lost. Bill
  2. Bill West

    Why does my post keep getting deleted?

    Curious, nowadays I thought a motorized desk in the den would be of much interest to the work at home crowd. Bill
  3. Bill West

    Gearmotor rotation question

    Hi Logic11. You can correct your industry under the blue tab at the top right, "My Stuff/MyProfile". The choices were in one of the pulldown boxes when you first registered, the box must have slipped on you while you were filling the page out. For your spec sheet its note of CW rotation is...
  4. Bill West

    Need 18V 1.5 amp motor having 200-400 maximimum RPM

    Hi Aces. Reddit just copies other forums, the catch is that some of those forums know less than you rather than more. The "when a motor is designed with a low RPM then the torque is high at the low RPM" understanding you saw is a classic incomplete statement. It should have had "for the same...
  5. Bill West

    Are ex-graduates second best to ex-apprentices?

    EnergyProfessional, good post. Some bits, it is only in the past 30 years that locomotive engineers in the US have been licensed and even then it is all to do with tracking serious rules violations such as running red lights or having an impaired driving conviction in an automobile. I legally...
  6. Bill West

    Are ex-graduates second best to ex-apprentices?

    MortenA & EnergyProfessional, it's a translation problem. In the US a 150 years ago, long before professional licensing, the guy who ran a locomotive was called an engineer not a driver and the guy who ran the boiler in the basement of every steam heated building was called an engineer not just...
  7. Bill West

    Carding Machine - Velocity of the rollers

    A little bit more about the rollers would help us see what needs to be sensed. Do the rollers have individual motors or are they on a common drive? If the latter why do you still get a speed variation between them? Are the rollers just driven by friction from the main drum? Is the gap/friction...
  8. Bill West

    Power transformer bushing test tap broken

    I would think that at the least the broken pin should be extracted and a new one installed in the cap. The insulation around the pin socket looks damaged but as it is grounded in service it would only be a problem during testing or if this was used for a bushing potential device. If the pin is...
  9. Bill West

    Neutral Current for CAPACITOR Unbalance Protection

    I think argotier has found the answer. Formula (13) at the bottom of page 12, simplified a bit in terminology is: Unbalance current = normal phase current/2 x [(C1f-C2n)/(C1f+C2n)] where C is capacitance of one branch, 1 & 2 are star 1 & 2 and f & n are faulty and normal conditions. We can take...
  10. Bill West

    Neutral Current for CAPACITOR Unbalance Protection

    A quick Google for "How do you solve an unbalanced 3 phase system?" brought up this video, https://www.youtube.com/watch?v=2vaxmirLd_k . I didn't go through it and I haven't done matrix math since college but I think putting 3 different capacitive impedances into it will give you the voltage at...
  11. Bill West

    Looking for design standards regarding naming convention of signal/control wiring

    A gate control is not complicated enough to need wire names. As long as the device terminal numbers/wire lead colours are on the schematic it should be easy to understand. If a wiring diagram is made then colours would be good, especially for wires going into cables or number tags for loose wire...
  12. Bill West

    Type of Contactor for Direction Change of Single-Phase IM

    At 1/30 hp we are below industrial sizes. The maker's diagram in Sham's photo is a bit weak, the literature at http://www.spg-usa.com/catalogs/induction%20Motor%20PDF/S8I25G.pdf shows the connections better. The maker has arranged the windings and the capacitor so that only a single lead has to...
  13. Bill West

    Neutral Current for CAPACITOR Unbalance Protection

    There is no meaningful current in the CT under normal conditions, not even if the 33kv is unbalanced. Current does flow in the CT when: -one of the capacitor cans becomes shorted, loses some of its capacitance or becomes open. (do the cans have internal fuses?) -manufacturing tolerances or...
  14. Bill West

    Conflict?

    phamENG's future home plans remind me that as the professional employees of a factory owner are certainly qualified to vouch for work in the factory it shouldn't be a conflict for the professional owner of a premises to do the same. The independent review is the AHJ. The counterpoint is your...
  15. Bill West

    Fishing for new projects with previous clients

    More general than getting work from existing clients, how about putting yourself in the shoes of someone who would hire your type of services? What would be your motivation to look for someone new -capacity? -quality? -cost? -personality? Then where would you look to solve that? In addition to...

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