Abb offers with various types of protection and control devices. Abb`s the spaf frequency relays are specifically designed for protection against frequency abnormalities in generators, motors and network. There are mainly two types of frequency relays and they are:
1 spaf 140 c - used for the protection of generators & other ac equipment against over and under frequency
2 spaf 340 c - applicable for load shedding in situations where power consumption exceeds the available power of the network