21Z Fault Impedance Calculator

Accurate fault location reduces operating costs by avoiding lengthy and expensive patrols. Accurate fault location expedites repairs and restoration of lines, ultimately reducing revenue loss caused by outages.

Several methods of estimating fault location are presently used in the field:
• DFR and short circuit data match
• Traveling wave methods
• Impedance-based methods
> One-ended methods without using source impedance data
(simple reactance, Takagi)
> One-ended methods using source impedance data
• Two-ended methods

This app uses simple reactance method for fault location calculation using relay fault record parameters. It is to note that fault location determination accuracy depends upon various parameters including fault type, fault resistance, source impedance, homogeneousness of line, remote feed etc. So, in all cases fault impedance based fault locator methods can not serve accurate result. However, it can be used as approximation\assumption.