Generator voltage regulator board(AVR) is a kind of low-frequency protection device to avoid breakdown or burning ring surge plates. LIXISE brand surge plates have a low frequency protection (UFRO) function, while we designed a low-frequency generator regulator board LED indicator (Figure 1 below) in EAVR16 generator voltage regulator board , when the low-frequency LED lights then you showed low frequency, low voltage, no current, then we need to do the appropriate remedy. Also for the generator on a "security firewall."

Where the low-frequency protection system must respond according to the frequency characteristics, and by close cooperation automatic frequency load shedding, the maximum possible reduction of the generator, the generator tripping.

Especially for the turbine, its low frequency protection is provided by the low frequency power system automatic load shedding to achieve. These low-frequency load shedding scheme should be designed at the maximum possible overload conditions, cut fast enough to load the system frequency back to normal. Frequency protection backup protection is usually installed on each generator using some of the low-frequency relays and timers to provide.

Frequency protection logic diagram below: