At 02:09 PM 2/17/2010, Stephen A. Lawrence wrote:
At the same time, there is one other piece of information which is missing, which makes it hard to judge the significance of the lack of measured change in the current: Does the motor slow down when the LEDs are turned on, and by what percent? If we assumed constant friction in the bearings, that would tell us what percent of the output power was being diverted from the bearings to the LEDs. However, the speed doesn't seem to have been measured in that test.
Right. However, notice that the LEDs cycle between bright and off. I think that the system may be speeding up and slowing down in response to the load. The voltage drops below that necessary to overcome the forward drop on the diodes, and then the motor speeds up, turning on the diodes, and then it slows down because of the braking effect of current being drawn....
Lots of details are missing that would enable a better judgment of significance, but he's giving far more detail than Steorn, which just says how little information Steorn has provided!
