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vasu.srinu001
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Per Unit Fault Calculation

12/19/2011 4:59 AM

what is the differance between

per unit fault calculation or fault calculation?
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PWSlack
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#1

Re: per unit fault calculation

12/19/2011 5:05 AM

At first glance, the words "per unit".

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kvsridhar
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#2

Re: per unit fault calculation

12/19/2011 6:40 AM

Try here

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jack of all trades
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#3

Re: Per Unit Fault Calculation

12/19/2011 1:00 PM

One's expressed in PU units (a unit-less expression related to the system), the other in units such as amps, volts and VA.

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wareagle
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#4

Re: Per Unit Fault Calculation

12/19/2011 5:11 PM

The per unit method is a way to make fault calculations.
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RAMConsult
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#5

Re: Per Unit Fault Calculation

12/19/2011 9:55 PM

The difference is the amount of time it takes to get the answer. It is easier to calculate the current through a reactance as 1/.05 and see that the current is 20 times the base current; rather than work with the actual phase to phase voltage, convert it to line to ground, divide that by the actual reactance in ohms to get a value in Amps, and then figure out how much greater than normal the current is. It is also how properly trained Power Engineers can spot wannabes during an interview.

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jack of all trades (1); kvsridhar (1); PWSlack (1); RAMConsult (1); wareagle (1)

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