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Rob, further to my earlier post! As you suggested, I reviewed your website. You are to be lauded for your project. The earlier kWh meter was based on the disk being rotated by an magnetically-induced torque resulting from power flow directed toward your home. The newer digital kWh meters...

Shahvir, The correct explanation can be derived from information I provided in my White Paper on "The Physics of... Armature Reaction!" If you want detail, let me know, either via the List or Off-List. However, please advise me if you have an aversion to the use of equations...

Rob, The utility is charging you for the cost of reactive Volt-Amperes (VAr) the induction-motor requires when used as an induction-generator! Look into providing the motor's reactive VAr requirement with three capacitors installed across the motor's terminals! Regards, Phil Corso...

Responding to Sunny’s 17-Aug-08 (09:55) query... Star-Star is preferred for two reasons: a) CT ratio's are easily determined. b) Earthing of the CT secondary wiring is simplified. Regards, Phil Corso ([email protected])

Responding to Ramesh’s 5-Aug-08 (00:12) request... following is a simplified discussion: A transformer’s impedance (also referred to as impedance-voltage) is equal to the voltage, in % of its rated-voltage, that when applied to the primary-winding of a transformer will cause rated-current to...

CSA, "droop" doesn't necessarily have to be linear. Phil

Nimra, My response related to your specific question about just two alternators in parallel has been covered in a previous post. CSA & CTTech, Past history suggests that to provide a "Physics of... Droop" topic would be futile. There have been some 300 threads covering droop. I contributed...

The motor is not OK! Tt's overloaded by about 22%. Scott's comment to check the input voltage is the proper next step! Phil Corso

CCTT & CSA, I don't know if your comments were meant to test my experience, veracity, age, or some combination therof. Also, I hoped this topic didn't start another brouhaha! But if you insist, then, a separate more focused topic entited, "The Physics of... Droop", should be initiated...

Liam, Your first concern should be the speed the DC motor in question must reach, i.e., 1500rpm! Regards, Phil Corso (cepsicon)

CSA and CTTech, I want to thank each of you for your invaluable critiques! They certainly were enlightening. Sincerely, Phil

CSA and CCTech, I don't understand your position(s), i.e., Critics w/o Critiques! Therefore, following is an abridged copy of the paper presented in January 2007, but without the items that seem to have you stupified such as illustrations, tables, formulae, phasors, or vectors: 1...

Bruce, 1) It is quite obvious that the system did not meet the definition of an infinite-bus. 2) It is quite obvious that the "computer" model was wrong! 3) Do you remember how the 200-km transmission-line was "modeled?" A short- or a long-line! 4) Do you think you can sent me a...

Anonymous, if you need only the variable-speed function, try this: Set the VFD to the motor's rated frequency, start the motor. Wait until it has accelerated to normal speed and the start-cap is disconnected! Then adjust the VFD to any desired speed! Of course, some precaution is...

CSA, I fully understand your reluctance to unburden yourself of a few questionable habits picked up during your years of experience. I know I still have many! Reminds me of a story! Three 3 hermits are sitting in a cave; soundlessly meditating life! One day an animal passes the mouth of...

Naga, I believe it’s best to answer your question by using examples. Hopefully, those who abhor formulas and equations won’t have a melt-down! The following should help: a) Consider two transformers, A and B, having equal capacity, voltage-ratio, and percent-impedance! They will each carry...

Responding to Krishna’s 25-Aug (11:20) query... No, it is not mandatory! For details, search the Control List Archives. There is a host of related topics! Regards, Phil Corso, PE

Responding to Aziz Al-Saffar’s 12-Jul (22:14) question: When rotor excitation was supplied through slip-rings loss-of-field protection was provided by undercurrent dc relays. But, such systems were subject to too wide a range of operating conditions. For example, they were susceptible to...

Anonymous, following is a list of many factors that must be considered: o Allowable voltage-drop for normal operating load. o Allowable voltage-drop for future operating load as determined by motor's Service Factor. o Allowable voltage-drop for starting condition. o Type of starting...

Responding to meshal's 13-Jan 5:12 pm comment, "... any step-down or step-up transformer... !" Do uou mean that any of the six transformers can be synchronized on either their 13.8kV or 123kV side?