AC-AC SSR 120A 3-Phase Solid State Relay, Input AC 70-280V, Output AC 24-480VProduct : Three Phase Solid State Relay Model: SSR 3 A4810 A4825 A4840 A4860 A4880 A48100 A48120 A48150 A48200 Current: 10A 25A 40A 60A 80A 100A 120A 150A 200A Controlmode : AC control AC Controlvoltage : 70 280VAC Load voltage : 24 480VAC Step 1: Choose a correct control Mode AA AC Control AC Step 2: Choose a correct type Current of Equipment Ratio = Current of SSR PS: The Ratio depend on the kind of your loading equipment. Resistive load : 70%,