initial fault & Ultimate fault

[SELEC]

I got some data from some utility company, they provided 'inititial fault & ultimate fault data',
I am not sure what they exactly mean? Are they minimum fault and maximum fault?

 

[itsmoked]

My (guess) the original response (exponential) followed by the steady state fault.

 

[dpc]

You should ask for clarification, but sometimes utility will provide actual fault data for the present system, but also give you a larger value indicating what the fault duty could be in the future, based on system expansion and growth.

 

[davidbeach]

Fault provided by the utility as presently constructed and fault provided by the utility after some future work (which may or may not occur)??

 

[SELEC]

I was told by my superviser that initial fault was Min. Fault Data, Ultimate fault fault is Max. Fault Data. But I doubt that.

 

[RonShap]

Initial: Fault current available today.
Final: Fault current available when they install the largest transformer upstream to serve your service.

 

[PaieMan]

Dear SELEC,

From my knowledge with my national utility company, when we asked for fault values, they will give the MINIMUM fault (say 4000 MVA and translated into kA @ 132 kV) and MAXIMUM fault (say 5600 MVA) values.

The maximum is what the utility has predicted now and some future forecast. They also need this for their own system protection planning eg. to consider for new equipment and planning for system expansion. And this value might change if the predicted generation/loads are confirmed.

The minimum is fault generated when minimum generation is connected to grid eg. during island operation of some of its power plants.

Not very sure of what your utility means but again, no harm in asking them. They could use a different software and the terms used be different?

My 1-cent opinion