Three-Phase Voltage control relay 380…480Vac, 2 C/O. range of product: Zelio Control – product or component type: modular measurement and control relays – relay type: control relay – network number of phases: 3 phases – relay name: RM22TR – relay monitored parameters: overvoltage and undervoltage detection, phase failure detection, phase sequence – switching capacity in VA: 2000 VA.