andrea.s
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- Member since Oct 12th 2014
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Posts by andrea.s
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See? I hadn't caught the tongue-in-cheek. No wonder: I would be one of those confined in the pidgin English ghetto thread...
Edit: but I got my apostrophes right unlike many native English speakers here..
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Perhaps there should be a rule that only people with a reading comprehension above a certain level can participate. I don't know how that would work in practice.
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Eric I normally appreciate your posts. In this case sorry to say but I find it hard to believe you entertain such a thought. Holy cow - this is a thread about Rossi, not Shakespeare or Wordsworth.
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Alan, Thank's for this lesson about [...] the English language.[...]
LDM may I ask where are you from? it intrigues me that you have this insider information about the Lugano authors.
And did you take a look at the spreadsheet and resulting COP when increasing the power input by lowering the triac delay. if you do believe as you say that a clamp may have been misplaced you may want to verify your statement about COP underestimation. It is underestimated at low drives as in the plots but largely overestimated when driving at AC Power representative of the test phase.
You sound honest and competent and I suppose you would admit it if your judgement were mistaken.
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How can a figment of the imagination be spoliated?
BTW spoliated to an Italian sounds like spogliato=undressed as if this were about virtual sex more than about a trial.
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I'm with you on this one. I would suggest Dott.Rossi (instead of Dr.Rossi) to make it clear that it is an Italian courtesy.
You see, I don't share the resentment against the man who has perhaps not invented the new fire, but whose deeds have emotionally involved and entertained all of us for so many years. If he gets into real trouble I would support an appeal for grace, though I may feel differently were it my money.
Edit: thinking it over, if it were my money, then it wouldn't be me.
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[...] in the US, this would be a Master of Arts or M.A. degree
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In any case, nobody in the U.S. uses the term 'Master' for people who have Master's degrees when addressing them (and of course we don't address people with Bachelor's degrees as Bachelor's). There is no special word for addressing someone who has completed either degree.
So in your experience in Italy, is there any specific way of addressing a person who has completed at Dottore Magistrale degree, or is that not done?
Do you ever use the term 'Dottore' in addressing a person with a Dottore Magistrale degree in philosophy?
Of course M.A. not M.Sc. , my mistake.
Yes it is common although old-styled to call Dottore, and address as Dr. Someone in writing, someone with whatever university degree.
That may explain why PhDs aren't that popular here. All those years and your title doesn't show up visibly to your neighbors and relatives unless you brag for it.
Italians are traditionally obsessed with titles, so we call people Avvocato (Lawyer) Ingegnere (Engineer) etc. which probably used to sound respectful a century ago.
I think I already mentioned a while ago that it is typical of illegal parking valets to call you Dottore in mocking reverence without caring to check your references. This applies to native Italians, whereas immigrants (the majority nowadays) use "capo" I.e. "boss" which is also pretty good for the ego.
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Thank you for confirming. It's especially helpful given that you are native Italian. I had made this point earlier about Rossi. It was based on a Milan student I met with a Dottore Magistrale degree (from the 'old regulations' that were in place in 1975 when Rossi graduated under the Vecchio Ordinamento ) who told me that he never refers to his Italian degree as a Masters, because it's really more equivalent to a U.S. bachelor's degree (even though it's a five year degree with a thesis) in terms of the amount of work and rigor.
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ditto, ditto...
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With that I must disagree. The new university system is now similar to the US with a bachelor and a master's degree in sequence. By no means the old system was less rigorous or easier. Universities now classify the previous degrees as a bachelor's or a master's equivalent based on their length and content. So if Rossi is a Dottore Magistrale you may well consider him a M.Sc.
Then in terms of quality and rigour one can have any opinion. When I studied engineering the American textbooks looked funny to me with lots of pictures and little theory. Italian texts in fundamental physics and maths were ugly and boring but much tougher. And when we wanted to challenge our skills with University colleagues we went to the Russian association library where books in physics and maths had the toughest exercises and problems ever...
On another note, to add to your list of dittos, one that amuses me is use of the (?) acronym AEG when referring to Ampenergo, just in order to impress whoever pays little attention with the resounding name of a historical German company (Allgemeine Elektricitats Gesellschaft) that -among else- built nuclear plants in Germany.
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Is there any truth to this?
As usual a half truth.
Rossy has a degree in Phylosophy.
Not sure whether it equates to a bachelor or a master, because at the time it was a 4 year course requiring a final thesis. edit: the attachment by Can shows it equates to a Master's degree.
In Italy you are called Dottore with such a degree.
To call it a Doctorate in the US is obviously misleading, as it is not a PhD. That would be a "Dottore di Ricerca" in Italy and require a couple years minimum research work plus a thesis after a Master's degree (with which you are a "Dottore Magistrale").
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[...] In addition to this I calulated also the situation in which I2 was reversed. The results are :
Both clamps correct 132.0 Watt
Clamp I1 reversed 168.4 Watt
Clamp I2 reversed -168.4 Watt
The last situation with a negative power would have resulted in the PCE 820 having displayed an error which would have been noted by the testers. Thus we can discard this situation.
In case of Clamp I1 reversed the testers would have calculated their COP value with a higher input power (164 instead of 132 watt) which would have resulted in a lower calculated COP value.
Thus measuring with a reversed clamp under estimates the COP ! This in contradiction to statements that the COP value would have been over estimated with a reversed clamp.
Was the clamp reversed ? I agree with your analyses that the clamp was probably reversed based on the figures of the currents of I1 and I2 displaying the same polarity signals. Since the PCE 830 was used upstream, Phase 1 was always present and not chopped so that the PCE 830 could trigger in the standard way. In that situation both currents should have shown opposite polarity (Good find !).
My preliminary conclusion is therefore that current clamp I1 was reversed and that this leaded to a too low COP calulated.
Hi LDM
First of all thanks for taking the time to comment on the spreadsheet.
The situation you describe is the one at low input drives that matches the pictures in the appendix. Triac delay is set to 143 deg, and indeed for these low powers (132W real, 168W when inverting I1) the COP is underestimated. The spreadsheet (mockingly) states "COP" 0.8.
Now if you change cell A3 "triac delay" from 143 to 87 and change Rload to 34.77 ohm to increase the input power in order to match the Ferrara March test (device named "HT2"), you get 2344W real, and 810W when inverting I1. The apparent "COP" is now 2,9 .
[ETA: replaced data of device "HT" with "HT2" as the Ferrara test was single phase for "HT2" only]
Herebelow an extract of the Ferrara report aka TPR1.
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Good catch, now that I've seen it I remember. Ok so there it is, very clear on a single screenshot and easier than a polar plot. So all we need is one of the Ferrara and Lugano testers to post a screenshot from each actual test. I have been asking for this since a few years. I received a private reply from Rossi, mostly based on arguments ad autoritatem, but nothing from the authors. Levi dismissed this idea on the blogs, which is understandable, but there are other five or six people who were there to review the work as peers.
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Energy values will not change, only power, but these should be instantly apparent as to what the problem is.
Embedded in the meter firmware should be
Power flow analysis including phaser diagrams, if a current transformer polarity is reversed, the voltage and current will show up in opposite quadrants.
As the load is primarily a heater there should be little if any reactive load, (power factor), so the current AND voltage should be physically close and in the same
Yes the load is a heater with negligible inductance, but the TRIAC control delays the turn-on of currents.
Nevertheless, the sequence in the vector diagram has to be the same : if it is V1-V2-V3 clockwise, it ought to be I1-I2-I3 clockwise. This could be checked for the Lugano test if a polar diagram were available.
In the TPR1 (black hotcat) where there is no I3 , it would be even easier: I1 and I2 must be in opposite quadrants. If they are overlapped it is proof of a reversed clamp.
Did anyone look at the PCE830 polar diagram in Ferrara or Lugano? I doubt. If they did, well: speak up!
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@IHFB
The individual phase powers (integral of Vj*Ij) are not shown by the PCE830.
The only way to notice is to look at current waveforms (and they weren't right so this should have been addressed) or vector display as in the pictures following (respectively correct and with I1 reversed)
Again: credits to GSVIT, Mario Massa in particular.
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No, there was zero current on the third clamp. And while a reversed clamp would alter the total power calculated by the PCE-830, the power for each individual clamp would be calculated correctly, just with a flipped sign for the reversed clamp. Do you mean to tell me that you don't think Levi checked the power for each clamp individually?
A clamp measures current, not power. If the clamp is reversed, the instantaneous value of current is read as its opposite. This is why the plots in the appendix are alarming: I1 and I2 are in phase instead of being in antiphase.
The reading on the PCE830 display will normally show rms voltages and currents (which are by definition positive figures), and the total power (which is instead the algebraic sum of instantaneous powers V1*I1+V2*I2+V3*I3 averaged over the period). I attach below a sample image (credits to the GSVIT guys).
[ETA: second screenshot is with one clamp reversed.. note the power sum dropping]
IH Fanboy, I am not saying any of this is proof. But it deserves a reply with facts and not a dismissal.
Consider that a clamp may be reversed by mistake, but also tampered with (inverting wires within).
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You are right on the absolute powers in the spreadsheet. At some point I reduced the step from 1 to 0.5 degrees to have a better resolution and forgot to correct the average formula (for twice the no. of samples). Thanks for spotting that.
This however changes nothing about the key point the spreadsheet wants to make, which is: when inverting a clamp (I1 in my spreadsheet) the power reading is wrong and the apparent COP varies with the conduction interval.
For low regimes it may go down to 1 or less, and when increasing the conduction time (thus average power) it increases arbitrarily. If the current weren't chopped at all, apparent power would be zero, i.e. infinite COP.
I will upload the corrected spreadsheet shortly.
[ETA: uploaded the corrected spreadsheet in .zip format as well hoping formulas are readable that way]
(.ods) https://drive.google.com/open?…ubncFIhCFaNF83OUgzUDcwenM
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I doubt you can compute mentally (let alone with a half brain) the power out of a chopped AC waveform. I propose you take a look at the spreadsheet. Then if something isn't right I will apologize and correct. LDM claims different results but it is hard to judge without a schematic diagram.
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Did you identify a mistake?
Can you show your diagram and the waveforms you are simulating? It is tricky to get the thyristor controls right. I did check my spreadsheet against a circuit simulator back then. Maybe we are assuming a different schematic.
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Did you note that the March test was single-phase?
The March test was done with a three-phase supply but a single-phase load.
With such a setup, an inverted clamp results both in matching the pictures in the appendix (where the currents I1 and I2 are suspiciously in phase instead of being out of phase) , and in underestimating the input power by an amount variable with the TRIAC setting.
This is more subtle than in the plain three-phase arrangement of Lugano where the misplaced clamp can only account for a COP of 3.
In the March test , when increasing the duty cycle one can get any apparent COP, for example the 5.6 claimed for the "HT1" device. At low regimes, the apparent COP decreases to 1 or less, which is good for making a low power calibration run credible.
I have made available a while ago a spreadsheet for anybody interested to play with.
[ETA: spreadsheet updated to correct an error spotted by @LDM]
https://drive.google.com/open?…ubncFIhCFaNF83OUgzUDcwenM
Just change the triac phase setting and you can get the (apparent) COP you like best.
[ETA: updated spreadsheet screenshots. Apparent COP goes from 0.8 to 5.6 by increasing the conduction interval from 1/5 to 2/3 of a time period]
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[...] I'll fiddle with the colors and see what it takes to get the magenta and yellows to display at the same time [...]
This is Obviously Paranoia.
You can get any temperature by playing with emissivity so why would they pull a Parkhy here?
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So; I'm trying to summarise the views from the few here who reckon IH is the Evil empire (or something more or less similar).
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I think there are three possibilities:
(1) They were convinced by early demos that Rossi is the real deal, the amateur positive results from Lugano-style reactors confirm this, and have never changed this view (type 1)
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My guess here is that:
Wyttenbach, Ele are type 1. Wyttenbach however does not see Penon data as conclusive, Ele does.
Ele? You classify him/her as a normal observer of this saga. I had a different impression. He/she has such a familiar style, with typical Itanglish misspellings and use of false-friend literary translations. Remember when he/she stood for Florida as the state of KSC against someone's criticism? Can you think of anybody else who would do that? Oh yes, perhaps SSC...
