Hi @AmmarKhalid -
If you tried to measure the wires in the motor wires going from thruster to ESC, this is actually an AC current and not a DC one! One wire only carries ~ 1/3rd of the total current being used by the motor. That’s why it’s best to measure the DC (red and black) wires going to the ESC.
It’s fairly unusual for an ROV to run all its thrusters at the same time, at the same thrust level. Additionally, if you’re using ArduSub, there is a built-in feature to automatically limit throttle levels to keep current draw below a desired threshold. Are you using BlueOS and ArduSub? If so, simply set BATT_WATT_MAX as desired - see more detail in this thread.