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Comment Re:I am Jack's total lack of surprise. (Score 3, Informative) 249

QA was probably done on linear loads which is where the meters would be accurate. On noisy switch mode loads (VSDs, computer power supplies, etc) there was probably minimal QA. Quite likely because regulation has not caught up with the prevalence of these loads. It is a case of meter manufacturers not keeping up with the time. And yes, I have seen this on a large scale; I ran into one power meter with a 200kW difference from the 1MW VSD it was down-stream of. And that was with some harmonic filters installed on the drive, yet the meter still read less than the drive. I'm inclined to suspect the meter here.

Comment Re: That's pretty smart (Score 1) 249

The issue is switch mode loads have non-linear current waveforms. What that means is if the meter, or clamp meter in this case samples incorrectly(Nyquist criteria), the current reading will still be wrong. You actually need a high sample rate power meter. Most commercial and industrial power meters seem to sample at 2kHz or less, which is fine for linear loads (even over-kill), but for say, a VSD or switch mode supply may be inadequate. Basically your clamp ammeter probably samples quite slowly as well.

Comment Re:This is awesome. (Score 1) 285

Ah, the lessor known theology which believes that you are selected for eternal damnation or heaven depending on whether or not you own a specific make and model of Van. Nobody knows what make or model that is, so you must preach Van buying to all.... ;)

As opposed to the Carminians who believe that anyone who owns a car, regardless can choose whether or not to go to speed week.

Comment Re:Wavelength can't fit within the universe(?) (Score 1) 532

E=hf and c=f(lambda) so, E=(hc/(lambda)). Thus wavelength is inversely proportional to energy. If energy is insanely small then wavelength will be high. What he is saying is that wavelength is 'quantumn' and can only take certain discreet values if it is very large.

Comment Re: receives 150,000 requests per second (Score 1) 78

I don't know about America, but over here I have seen the frequency vary from 49Hz to 52Hz as the grid gears up for the 6am winter load(everyone gets up and starts cooking/boiling a kettle etc). On average it is still probably accurate. I am fairly sure the US power companies do the same thing. It is difficult to control the frequency under varying load.

Comment Re:It's getting there but big franchises still mis (Score 1) 179

I don't know about i3s not lasting. Maybe not for the PC 'master race', but for the rest it might be fine. My last machine was fairly cheap (Phennom II X4, worse than an i3) and it still goes well. Still in use - my wife plays casual games on it just fine. Seems to perform OK for even modern titles (only thing I did was put a GTX750 in it, because the 460 died).

It may be ill advised, but they really seem to be pushing into the console market. Apart from Source 2, DOTA 2 and VR, which can fit that strategy. I don't see a valve game in the near future. Call me a pessimist, but I don't think they have been a proper games company in a while....

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