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Point-to-point method
- Thread starter chrust
- Start date
Skogsgurra
Electrical
"Connect-the-numbers" perhaps?
Sorry for that. Do you mean point-to-point communication? One alternative name is peer-to-peer communication.
Gunnar Englund
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
Sorry for that. Do you mean point-to-point communication? One alternative name is peer-to-peer communication.
Gunnar Englund
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
I forgot to answer the question, sorry:
"The point-to-point method, sometimes referred to as the direct method, is a progressive analysis of the electrical distribution system."
from
"The point-to-point method, sometimes referred to as the direct method, is a progressive analysis of the electrical distribution system."
from
still inconclusive...analysis for what? cost? reliability? short circuit current? arc flash? transient study? load flow? Color of equipment?..
Where are you reading this? You can't expect any useful answer until you can make it clear as to what you are looking for. People here are not mindreaders. Your statement is gravely nebulous.
Where are you reading this? You can't expect any useful answer until you can make it clear as to what you are looking for. People here are not mindreaders. Your statement is gravely nebulous.
Quote from
(as was my previous posting)
"You can calculate the 3-phase short-circuit current at each location using one of the following four methods:
Ohmic method
Per-unit method
Computer software method
Point-to-point method
The ohmic method is useful for very simple electrical systems. It depends on calculated ohmic values to determine the short-circuit current at each designated location. However, the ohmic method doesn't generally apply to industrial or commercial systems because it's difficult to convert ohms from one voltage base to another without error. In addition, the small numbers used in the calculation process make accurate calculations tricky.
The per-unit method is useful in more complex designs, particularly when you must consider several voltage levels. It is more representative than the ohmic method when performing a conventional electrical circuit analysis. It establishes base, or reference, values for volts, current, kVA, and ohms and then refers the actual parameters of the system to these bases in equations to establish per unit values for each. Applying these values in unique equations provides the calculated short-circuit values.
The computer software method is the most popular because of its speed, ease of use, and ability to run multiple system design scenarios. Software calculates the short-circuit current at each selected location based on the point-to-point or traditional method, the per-unit or ANSI method, and — more recently — the IEC method.
The point-to-point method, sometimes referred to as the direct method, is a progressive analysis of the electrical distribution system. Starting at the source, you analyze each section to determine the short-circuit current at each designated location down to the end of the various circuits. Separately consider each point of fault."
See the link in my first posting for more details.
(as was my previous posting)
"You can calculate the 3-phase short-circuit current at each location using one of the following four methods:
Ohmic method
Per-unit method
Computer software method
Point-to-point method
The ohmic method is useful for very simple electrical systems. It depends on calculated ohmic values to determine the short-circuit current at each designated location. However, the ohmic method doesn't generally apply to industrial or commercial systems because it's difficult to convert ohms from one voltage base to another without error. In addition, the small numbers used in the calculation process make accurate calculations tricky.
The per-unit method is useful in more complex designs, particularly when you must consider several voltage levels. It is more representative than the ohmic method when performing a conventional electrical circuit analysis. It establishes base, or reference, values for volts, current, kVA, and ohms and then refers the actual parameters of the system to these bases in equations to establish per unit values for each. Applying these values in unique equations provides the calculated short-circuit values.
The computer software method is the most popular because of its speed, ease of use, and ability to run multiple system design scenarios. Software calculates the short-circuit current at each selected location based on the point-to-point or traditional method, the per-unit or ANSI method, and — more recently — the IEC method.
The point-to-point method, sometimes referred to as the direct method, is a progressive analysis of the electrical distribution system. Starting at the source, you analyze each section to determine the short-circuit current at each designated location down to the end of the various circuits. Separately consider each point of fault."
See the link in my first posting for more details.
Good work!! Now you are talking. (I would prefer that the person asking the question does the required legwork).
No there is no other "name" that I am aware of for this “method”. In fact I seldom use this method, it works for simple radial system and uses obscure constants published by some cable manufacturers to come up with some multipliers, etc. In my opinion it is not a very scientific way, but it does work when used correctly.
Also modem soft wares have made such methods, almost obsolete.
But if you want to know how it works, one of the free references is the "SPD- Electrical Protection Handbook", published by Cooper Bussman. It may be on their web site or your local rep can help you out or call them.
If you are trying to learn how to perform short circuit calculations, you are much better off ignoring this method.
Good Luck.
No there is no other "name" that I am aware of for this “method”. In fact I seldom use this method, it works for simple radial system and uses obscure constants published by some cable manufacturers to come up with some multipliers, etc. In my opinion it is not a very scientific way, but it does work when used correctly.
Also modem soft wares have made such methods, almost obsolete.
But if you want to know how it works, one of the free references is the "SPD- Electrical Protection Handbook", published by Cooper Bussman. It may be on their web site or your local rep can help you out or call them.
If you are trying to learn how to perform short circuit calculations, you are much better off ignoring this method.
Good Luck.
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