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Responding to erik's Sun, May 30, 12:16pm query: If you are unable to obtain information from a motor manufacturer's data sheets, then I suggest you use the following reference: Baumeister and Marks, "Standard Handbook for Mechanical Engineers" Publisher, Mcgraw-Hill, USA. Regards...

Corrections to my Mon, May 17, 2:56pm reply: 1) Per "The Start-Winding Circuit." 2nd sentence should be: The start-winding current is inversely proportional to the vector addition of Rw, Xw, and Xc. 2) Per "Life Expectancy Improved." 1st sentence should be: No one will argue...

Get a copy of my paper... "Probability Risk Assessment of Equipment Safety Systems" Search A-list archives for details! Regards, Phil Corso, PE {Boca Raton, FL, USA} [[email protected]] ([email protected]) {[email protected]}

Responding to Confused's May 10 query & May 13 comments: If I have interpreted you correctly... you want to know if changing of the start capacitor's rated voltage will impair the motor? To impart some basic knowledge while dispelling some of the misconception advanced thus far, following is...

Responding to pbw's Fri, Apr 16, 1:19 pm comment: Caution: The transformer is a three phase unit. Thus load current is not 36 A, but instead, 21 A. In most 4.16 kV installations the wire size determination is dictated by short-circuit withstand duty, never load current alone. Also...

List: Not a good idea to provide this info to someone called "anonymous!" Regards, Phil Corso, PE {Boca Raton, FL, USA} [[email protected]] ([email protected]) {[email protected]}

Responding to Kevin's query... Which of the four "Surges" that come to mind are you interested in: 1) Surge Impedance as related to transmission line characteristics. 2) Surge Impednce as related to loading of a transmission line. 3) Surge or asymmetrical or crest factor for short...

Responding to Looniebunny's query: Hopefully, the following are the four you need: 1) The usual expression, when the total losses are known for a particular load, then: %Eff = 10^2 x Output / (Input + Losses) 2) If % iron losses, Pi, and % copper losses, Pc, are known for a...

To Anonymous, In my experience, although flame-rod flame-loss detectors are very reliable, they are a high maintenance item. Their failure vs time characteristic do not follow the conventional "bath tub" curve. Thus, in many refineries and chem plants it is standard practice to assign one...

Responding to Rahul's incredulity... monitoring of normally-closed contacts has been in use for about 25 years now. Open-circuits, short-circuits, and ground-faults (earths) can be (simultaneously) detected! Such monitoring is essential for effective improvement of SIS reliability...

To List, Earlier post omitted the sqrt function in the denominator. PF formula should be: PF = kW / sqrt [ kW^2 + kVAr^2 ] Regards, Phil Corso, PE {Boca Raton, FL, USA} [[email protected]] ([email protected]) {[email protected]}

Responding to J.Wong's Sun, Apr 4, 11.26 am, query: See my explanation in the Journal of the System Safety Society, "Hazard Prevention" Title: "Probabilistic Risk Assessment of Equipment Safety Systems" Issue: Vol 35, No. 3, 3rd Qtr, 1999. If you are unable to obtain a copy...

Responding to Accord. K's, simple question: Here is a simple answer... and by no means the only one: Consider the motor an R-L circuit. R produces torque and requires "real" power, kW, from the supply. L produces the magnetizing needs of the motor, and requires "reactive" power, kVAr...

Responding to Kchishti's Mon, Mar 29, 1:51pm query: 1) Dimension Error? If the output power is 5 kW, then rated torque at 3570 rpm is 1.37 kgf-m, or 13.4 N-m. 2) Substitution Considerations. a) If your intent is to substitute a "near" standard induction motor, then a 50 Hz, 2-pole...

Responding to M. Sriram's Mar 15, 10:58pm, query: Are you seeking information regarding CT Saturation as applied to protective relaying applications? That is, the cause of, the consequences of, and corrective actions to reduce, saturation? Regards, Phil Corso, PE {Boca Raton, FL, USA}...

Responding to FLH's Mon, Mar 15, 8:37pm query: The formula for fundamental frequency is unaffected by capacitor configuration. However, the resutant value will change! Regards, Phil Corso, PE {Boca Raton, FL, USA} [[email protected]] ([email protected]) {[email protected]}

This is in response to Anonymous' Fri, Mar 5, 6:19pm query: I investigated a problem similar to this about 2 years ago, except there were two MV gensets, and one LV genset. In order to provide you with meaningful answers, please comment on my interpretation of the information you provided...

For Dick, "Hear, Hear" Regards, Phil Corso, PE {Boca Raton, FL, USA} [[email protected]] ([email protected]) {[email protected]}

For Peter: Thanks for the 'heads up' advisory! Regards, Phil Corso, PE {Boca Raton, FL, USA} [[email protected]] ([email protected]) {[email protected]}

Resonding to Pat Hutchinson's query: 1) What are the corresponding ph-to-ph voltages? 2) Are they VFD driven? 3) Are the pumps constant displacement? Regards, Phil Corso, PE {Boca Raton, FL, USA} [[email protected]] ([email protected]) {[email protected]}