[Al Skierkiewicz]

Chris,
The diodes only conduct when the EMF is higher than 2.5 volts above the battery voltage. This will only occur (theoretically) during the inductive spike. The EMF is lower than the applied voltage except if the motor is supplied mechanical speed at greater than the applied voltage would produce. You also want to consider that the current only flows when a circuit is closed. Once the diodes stop conducting, there is no where for the current to flow. Open circuit voltage rules apply, even though the difference is small. I think that actually works in your favor if you are considering high impedance voltage monitoring. I have no specifications on the inductance of the motors. However the L/R equations go out the window with no current flow don't they?