Dont worry too much about the DDP voltage. Actually the voltage adjustment is really just a duty cycle adjustment. The manual won't explain that. The higher the reading the closer you are to 5050. The bigger issue is knowing how to shift the sensors to achieve the correct phasing between DDP1 and DDP2. The hall sensors can be cheated in or out a small amount by rotating them about 1/2 turn. They look like they are in the center of the plastic sensor body, but you can make minor adjustments to them. This if done properly will give you the correct phasing to get rid of floor counting errors.