Jed,
The DC and AC act independently of each other in this case. Even thought the net flow might be one direction, the time varying portion (AC) reads the correct value. You can think of DC as being very low frequency AC and the power delivered by each component can be calculated separately. Take the RMS voltage of the AC source and multiply it by the RMS current at the fundamental frequency of that source and you get the true power delivered. Of course the phase difference between them needs to be taken into account. For DC, it is just the DC voltage multiplied by the DC current that matters. Add these numbers together and you get the total power absorbed by the load. The only time DC power is delivered by the source is when a DC supply is connected in series with the AC that is normal. Of course, anything of that nature would be a scam and easy to detect. Dave -----Original Message----- From: Jed Rothwell <jedrothw...@gmail.com> To: vortex-l <vortex-l@eskimo.com> Sent: Wed, Jun 26, 2013 8:10 am Subject: Re: [Vo]:Face-Palm moment: Essen et al did it again! [Abd's open letter] I am pretty sure they did bring other instruments. I can ask. As I mentioned, in previous studies Levi brought a small $20 wattmeter, similar to a Kill-a-watt. (A European brand; I have forgotten the name. I have a photo of it somewhere.) John Berry <berry.joh...@gmail.com> wrote: It depends of the magnitude of the DC in relation to the AC. If the DC bias was equal to the AC peak voltage, then the current would not reverse. And the peak voltage in the biased direction would have doubled. Okay, bear in mind it has been 40 years since I learned anything about electricity . . . Let me see if I understand. You are saying than when current does not reverse it is DC. It is by definition -- rapidly fluctuating but all positive. The meter would suddenly see no electricity. As long as it does reverse, it is AC and the meter would detect it. It would see it as AC with a huge bias. Meters have to be able to see this because a DC bias is a common problem. In this actual case, the power appears to be on one-third of the time and off two-thirds. In the "extra DC" scenario it would actually be on the whole time, and at a higher level when the AC seems to be off (to prevent it from going negative). In that case the temperature would not track the power input. It would not fall when the power goes off. - Jed
