The ability of a system to react to a change in system frequency.
Relevant items: Primary Control
Frequency Response
(Equipment) The ability of a system or elements of the system to react or respond to a change in system frequency.
(System) The sum of the change in demand, plus the change in generation, divided by the change in frequency, expressed in megawatts per 0.1 Hertz (MW/0.1 Hz).