The Transmission Company of Nigeria (TCN) has said the collapse of the national grid on Wednesday was due to a sudden drop in the system frequency.

The TCN General Manager, Public Affairs, Mrs Ndidi Mbah, made this known via a statement issued on Thursday.

Mbah said the national grid experienced system disturbance at about 11:27 a.m. on Wednesday, noting that its restoration was almost completed as of 11:00 p.m.

”The incident was a result of sudden drop in system frequency from 49.94 Hertz (HZ) to 47.36Hz, which created system instability,” she said.

Hertz is a unit of frequency which replaces the earlier term of one cycle per second (cps).

READ ALSO: Atiku condemns incessant national grid collapse, proposes solution

Mbah stated that reports from the National Control Centre (NCC) revealed that the collapse was precipitated by the tripping of a unit with a load of 106 Megawatts (MW) in one of the generating stations due to “Exhaust over Temperature”.

She noted that the tripping pulled out other grid-connected units in the plant, which resulted in aggregated generation loss of 457MW.

“A train of events ensued, culminating in the collapse of the national grid.

“As obtainable in all systems, when a component of the electric power system is defective, the entire configuration is vitiated,” the TCN general manager added.

Mbah said an investigation was ongoing to establish the cause of the failure.

The Star