As long as we're waking up the old thread...
If you are using a current transformer to read the current in a split-phase feed, you only need one current transformer (or clamp-on meter). You just put the two hot lines through the core in opposite directions (i.e. cross them over in an X and clamp the meter onto the crossover, or push them through the toroid in opposite directions).
You should be able to use one of the little semiconductor wattmeters on the voltage (of either half of the split phase if it's a 120v memter) and the output of the current transformer (which may need scaling by changing the shunt in the meter circuit to a moderate value resistor).
Next step, though, is translating the meter display into control information for your charger or its control computer.
