Detail Reyrolle Argus 8 7SG1183-4UE21-0DA-Z S06
7SG118 relays provide under/ over voltage and optionally under/ over frequency protection. Generally these relays are connected to the secondary windings of VT circuits, however an external adaptor unit is available where used with capacitor cones commonly found on distribution networks. 7SG118 voltage relays are typically used in control and interlocking schemes, frequency relays are typically used in load shedding schemes.