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Responding to Rajesh's Wed, May 1, 4:13 pm, query: I'm not sure about your requirement for a "Finite Element Method!" However, If you mean a method for determining the distribution of line-to-ground (earth) potential across an insulator string of discs used in overhead power lines, then I can...

I normally don't mix in when it comes to politics, religion, and sex, but the current difference of opinion reminds me of the story of 3 hermits living together in the same cave: One day a horse passes the cave. A year later one of the hermits slowly says, "did... yuh... see... the... cow?"...

I suggest the IEEE Std 100-1992 "The New IEEE Standard Dictionary of Electrical and Electronics Terms" for the definition of Redundancy and Standby BTW, if you don't have access to the std, let me know, and I'll send you the definitions! Regards, Phil Corso, PE (Boca Raton, FL)

Further to my earlier response... another "BITE" story: I must be honest. I wasn't told about the car's selector switch. I actually worked with an elderly gentleman that owned such a car. Charlie, as he was called, was a Scotsman, and he was known to be quite frugal! One day, Charlie...

The original term "freewheeling" was related to device(s) that allowed power transmission shafts to rotate "freely" when its speed was greater than that of the engine to which it was connected. In fact, I'm told, in the cars of the 20's and 30's a selector switch was installed on the steering...

Contact: University of Texas (Austin), Balcone's Center for Electromagnetics. They developed shunt devices for Mega-ampere circuits. Regards, Phil Corso, PE (Boca Raton, FL)

Curt, I apologize. My response was too quick. You are correct for the case where a coil is subject to an overvoltage that drives its magnetic structure into saturation. Then, the temperature-rise-above ambient will be proportional to the square of the current-ratio. Remember the halve rule -...

It is strange observation. Usually an increase in operating voltage to an electromagnetic device, like a solenoid, will result in a lower current, hence a lower temperature-rise above ambient. However, this is only true if the device is in a normal operating condition. What is the "on/off duty...

Your condemnation of diodes is unfounded, at least in my experience. I have used diodes as transient suppressors for DC coils for at least 4 decades. NEVER HAD A FAILURE. Of course, they must be properly rated! However, I do warn my customer base that a high rate of coil interruption will...

For those of you hellbent on connecting two or more induction motors in a "load-share" arrangement: In most cases it can't be done. Please search Archives for previous threads which provide the theory and examples: "Motors in Tandem" "Motors Assisting One Another" "Conveyor Belt...

Why not use a 24 Vdc interface control relay, mounted in/at the starter, to switch the 230 Vac contactor coil? Of course, regs/stds/ap's covering wire/circuit/source/location must be applied. Regards, Phil Corso, PE (Boca Raton, FL)

Terence: You are to be lauded. Just a few List contributors would ever 'fess up to having made an error Regards, Phil Corso, PE (Boca Raton, FL)

Responding to Dom's Thu, Mar 14, 12:01 pm comment: You need the newer 85 series of the NFPA regs. They have incorporated more restrictive measures. If PLC's are involved, then, hardwired circuitry is also required. The implication is quite clear (at least to me)! Regards, Phil Corso, PE...

Technology transfer for political gain occurred long before the internet was a gleam in some learned person's mind's eye! Regrettably, in the '60's I was one of those "pawns" in the technology transfer game. Its purpose (I was told) was for the good of resurrecting Europe. Ah the innocence...

For Ting: Yes, there are 24 V LED's. The required resistor is "built-in!" Regards, Phil Corso, PE (Boca Raton, FL)

For Pete: If you are in the USA go to Radio Shack, or their parent company Tandy Corp, and buy their "Green" primer: Getting Started in Electronics" Author, Forest M. Mims, II RS Cat No, 62-5003 Regards, Phil Corso, PE (Boca Raton, FL)

Search the List archive (this website), late Sep 2001, for discussion on Dielectric Test procedure and evaluation of resultant measurements. Regards, Phil Corso, PE (Boca Raton, FL)

Responding to Mario Roberto's query: Be careful about naming heat recovery boiler a "flue gas cooler". Plant I worked for was heavily fined when the country in which it was located ruled that it was indeed a Heat Recovery Unit and not a gas cooler. As to PID info, search List archive for...

DC current calculation using two or three of the stator leads for either wye or delta windings as well as theory was presented to List about Dec 01 thru Jan 02. Search archive for: ENGR: AC Motor Braking. or APPS: Induction Motor Braking. Regards, Phil Corso, PE (Boca...