SCADA: A System In Action In A Campus

Fault Location Without SCADA

Things were grim in the early nineties before introduction of SCADA technology. There was no clear-cut method to determine the magnitude of power failure in a campus. Primitive methods like waiting, guessing, luck factor, triangulation, etc. were depended on to find out the affected buildings and ways for restoring power.

Triangulation

Lot of people was involved before SCADA in the process of identification of power failure ranging from customer service people to building managers to the high-volt electricians. The particular branch of a circuit where the power had failed could not be known and the failed area of the distribution system could only be found by applying a method of triangulation after identifying a number of buildings without power. It took many hours and an elaborate procedure like triangulation to trace the source of this power failure. Each fault indicator on a distribution cable located underground and spread over a large area had to be examined by the attending crew by removing vaults and manhole covers. Location and restoration time of faults were thus long. SCADA system has totally eliminated this cumbersome procedure of fault location and servicing. By doing post-failure analysis, SCADA prevents recurrence of such failures.

The Changes

System operators are now able to obtain immediate and remote status changes as the systems under SCADA are connected by multiple high-volt switch contacts. Other than the need to locate the fault, there was need for HV technicians to determine the existing use of specific distribution cables for the purpose of record and evaluation. Now SCADA provides detailed periodic reports enabling the switching operators to transfer load in case of necessity to other feeders in the system. This information was earlier obtained from feeder ammeters in a sub-station which took a lot of time. Before the use of remote SCADA application, there was no way the physical changes in operator switch position could be confirmed.