Does Motor Protection IED use motor nominal or CT nominal for protection? Are residual currents also scaled?

Does Motor Protection IED use motor nominal or CT nominal for protection? Are residual currents also scaled?

By default all AQ-200 series Motor Protection IEDs use scale current pick-up settings to current transformer nominal values. If the settings need to be scaled to the motors nominal current instead navigate to Protection > Motor Module > INFO and change Per unitize relay currents to motor In to Yes, scale all to Imot. When this setting is in use the relay scales all current based protections pick-up settings to Motor nominal current setting. Please note that you should still set the CT ratio at Measurements > Transformers > CT module to get proper measurement scaling.

Please note that the residual current channels Io1 and Io2 are not affected by this setting. They will always follow CT nominal values set at Measurements > Transformers > CT module.

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