Where do we use current transformer operated overload relay / Electrical

[@jordaoantonio808]

thank you Sir. Absolutely helpful

[@ElectricalPlatform]

Thanks

[@adelhesham8143]

🙏 Thanks but‚ Can I ask why we don't use normally use regular thermal over load with CTs for all motor ratings ? Not Just after 200 A motor ratings only ?

[@ElectricalPlatform]

When cable size increases , cable would not terminated on relay ., so we use CT to reduce current and the secondary smaller size cables would easily get terminated on relays

[@adelhesham8143]

@@ElectricalPlatform So do you think I can use it on any load as long I keep the conversion ratio ? Like a motor with a 30 or 40 Amp And using CTs with 50/5 ratio And a small overload like 2.5-4A or 1.6-2.5 A