Can i use this sensor to measure an rms of 50 A and peak of 150A
No, I'm afraid not. We use this Infinity Sensor for double pulse testing at the values you state, but not for continuous switching, since it would overheat. Also, it's worth considering that the Infinity Sensor is for looking at fast switching edges, not the whole waveform. For that it would be better to use a Rogowski coil, so as those offered by PEM Ltd.
I could imagine that working. Let us know how you get on. You could try a shunt measurement on the secondary side current transformer instead of buying our sensors.
can you please give us a bit more insight on when exactly the sensor overheats?
Up until now, I did not realize that overheating could be a problem.
Please see our answer to your question in the thread you created. Let us know if that answers your question please.