If you are intending to use a data logger to take the measurements, I would recommend 2 x ADC212/3.
To measure the voltage you will also require an isolating probe x10/x100.
To measure the ampage I would recommend three 300A current clamps to be used with the ADC212/3. To connect the current clamp to the unit you will need 3 x TA000 test leads.
To convert the voltage reading into an ampage reading you will need to use a scaling file. All this can be done with Picolog software. It can take multiple channels and allow datalogging with 1 ms intervals.
The details an cost of these items can be found here