Measuring 200A - 400A AC current using arduino.

I'm looking for a way to measure AC current from a 250HP motor which draw around 250A(350A at maximum) using arduino, is it possible to do it with this circuit&sketch

https://learn.openenergymonitor.org/electricity-monitoring/ct-sensors/how-to-build-an-arduino-energy-monitor-measuring-current-only

and this CT : https://www.aliexpress.com/item/33035621426.html

if it is possible, which value of burden resistor I need to use or is there anything I need to add or change in the circuit?

Thanks in advance.

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I'm looking for a way to measure AC current from a 250HP motor which draw around 250A(350A at maximum) using arduino, is it possible to do it with this circuit&sketch

How to Build an Arduino Energy Monitor - Measuring Mains Current Only — OpenEnergyMonitor 0.0.1 documentation

and this CT : https://www.aliexpress.com/item/33035621426.html

if it is possible, which value of burden resistor I need to use or is there anything I need to add or change in the circuit?

Thanks in advance.

That big of a motor MUST be running on 3-phase power, probably at around 450 volts AC. So you will need three current transformers, each able to measure the STARTING current of the motor, which may be the 350 amps you mention.

Paul

To calculate the burden resistance do it the easy way use a calculator: CT Calculator From what I can derive from you question it is probably operating on 480 or 575 volts (nominal voltages). The circuit should work just fine. Be sure it is powered down and locked out before you attempt to install the CTs. This response is to help you get started in solving your problem, not solve it for you.
Good Luck & Have Fun!
Gil

Note that the max load for the various CTs is given, the 400A version is limited to 1VA, with an output current of 5Arms, thus its burden resistor MUST be 40 milliohms or less, including wiring. This will give a maximum output voltage of 200mV rms

This is not a suitable device for use with an Arduino where you want volts of signal at full-scale.

400A in and 5A out is a ratio of only 80:1, you want something more like 1000:1 to 5000:1 range.

Alternatively directly connect it to a smaller CT with 5A input and a reasonable output current level.

The easiest option is to buy a current transducer that has a 4-20mA output that you can use almost directly with Arduino . It take care of converting the output to DC for you and is a simple safe solution.

If your motor has a balanced supply then you can use just the one .