Problemer med Scotte Blackstar

[pille bruger]

[quote="motoz"]I don't get it, why would it not show correct "effekt" in the display at low power? If the "snegl ydelse" parameter is set correctly then it should know exactly how much pellet is fed for every second that the screw is running?

Fordi smuld kan forstyrre udmålingen.
Så er den ikke præcis mere.
Du afvejer jo ved at veje piller og smuld, men smuld blæse af herden, og giver ikke varme.
Derfor skal man altid se og bedømme flammen ved at kigge ned i fyret, og ikke ved at se en Kw på display.

Or do you mean that you can expect to get 1kW of heat, when feeding 2kW pellet, if min_effekt needs to be raised to 2kW to get a clean burning flame? That would be quite awful...[/quote

1 kw. indfyret pillemateriale, giver 1 Kw varme, men får fyret ikke 1 Kw indfyret materiale, pga. smuld eller andet,
kan man kompensere for manglende materiale ved at ændre i tilførslen.

[motoz]

Thank you for bearing with me! (I'm not trying to be difficult, I'm just curious by nature. Please keep in mind that English is not my first language)

That was the clarification I was looking for, that it's the fine fraction getting blown off the grate.

Then it's just one more thing left...
If it burns just 1kW when feeding pellet for 2kW at 10% modulation, that would mean that 50% of the fed mass is getting blown off the grate without being burned. OK with that.

But why does not the same happen at full power? It is still feeding the exact same pellet/fine-fraction composition, and the fan setting is much higher, so I think it would blow even more stuff off the grate then?

[pille bruger]

Thank you for bearing with me! (I'm not trying to be difficult, I'm just curious by nature. Please keep in mind that English is not my first language)

That was the clarification I was looking for, that it's the fine fraction getting blown off the grate.

Then it's just one more thing left...
If it burns just 1kW when feeding pellet for 2kW at 10% modulation, that would mean that 50% of the fed mass is getting blown off the grate without being burned. OK with that.

But why does not the same happen at full power? It is still feeding the exact same pellet/fine-fraction composition, and the fan setting is much higher, so I think it would blow even more stuff off the grate then?

Det er lidt mere nuanceret end som sådan.
For lange piller - svag start kondensator i sneglen - hårde piller - smuld - fugt i pillerne + mange flere ting,
kan have indflydelse på hvor mange piller der udføres, hver gang sneglen giver en dosis.
Hvis dosis er 100% ens hver gang, og alting kan brænde ved den angivne brændværdi er udmålingen i effekt på display rigtig.
Men sådan en perfekt situation findes ikke.
Derfor kan man korrigere og finindstille ved lav effekt.
Ved fuld effekt, vil pilletilførslen være hyppigere, og udsving derfor af mindre betydning.
Pille bunken med ild i vil være større og brede sig over et større areal på herden,
og smuld vil derfor kunne lægge sig i bunken uden at blive blæst helt væk,
og derfor også bidrage mere til at lave varme.

[motoz]

Sure, but since the "snegl ydelse" parameter is set according to a 6 min average, these fluctuations should average out equally well at max power and min power. Why would it on average be correct at full power but not at min power?

I still don't see why the power level on the display wouldn't show exactly how much pellet / second I am paying for right now, which is what I expect the reading to show me. If it's trying to guess the efficiency of the burner/boiler combination at the current power level to show the real power used by my house then I guess I have no use for the reading at all, because then it's just guesswork anyway.

[pille bruger]

Sure, but since the "snegl ydelse" parameter is set according to a 6 min average, these fluctuations should average out equally well at max power and min power. Why would it on average be correct at full power but not at min power?

Fordi variationen i doseringen ved fuld last er mindre betydende, sammenholdet med de udsving i smuld eller andet der kan variere.

I still don't see why the power level on the display wouldn't show exactly how much pellet / second I am paying for right now, which is what I expect the reading to show me. If it's trying to guess the efficiency of the burner/boiler combination at the current power level to show the real power used by my house then I guess I have no use for the reading at all, because then it's just guesswork anyway.

Hvis styringen viser 2.6 Kw og flammen er mindre end et fyrfadslys, vil du så forvente at der afsættes 2.6 Kw ?

[motoz]

If the display shows 2,6 kW then I would expect the burner to eat 2,6 kW / 4,8 kWh/kg = 0,54 kg/h. Or about 10% more if some probable efficiency is taken into account, but I would appriciate if that would be written in the manual so I wouldn't have to guess.

I am very aware that the burner have no way of knowing how much of that power goes into the boiler water and how much is fed up the chimney as pollutants, so I would absolutely not expect that number to tell me anything about that.

[pille bruger]

If the display shows 2,6 kW then I would expect the burner to eat 2,6 kW / 4,8 kWh/kg = 0,54 kg/h. Or about 10% more if some probable efficiency is taken into account, but I would appriciate if that would be written in the manual so I wouldn't have to guess.

I am very aware that the burner have no way of knowing how much of that power goes into the boiler water and how much is fed up the chimney as pollutants, so I would absolutely not expect that number to tell me anything about that.

I det tilfælde skal du bruge iltstyring og flowmåler.
Så kan du få den udlæsning, men som basis kan du ikke forvente at teori og virkelighed altid stemmer over ens,
pga. de allerede forklarede unøjagtighedder.
Derfor har du mulighed for at justere så tingene tilpasser sig hinanden.
Det er derfor manualen beskriver hvordan man justere forbrændingen.

[motoz]

I am probably very bad at explaining what I'm trying to ask. I am very satisfied with my burner and how it works AND how you adjust it for correct burning.

It's just that it is often mentioned in these forums that the "power kW" indicated can not be trusted on low power, and I want to know why.

IF (a) the "power kW" reading works as I expect and describe above, then the issue is that other people expect other things from it, and I'm still satisfied.

IF (b) it somehow by guessworking tries to show something else, then that's OK too, I'll just ignore the reading from now on as it tells me nothing. I can still calculate it myself from the feeder-screw run time.

But which one is it? A or B?

[pille bruger]

I am probably very bad at explaining what I'm trying to ask. I am very satisfied with my burner and how it works AND how you adjust it for correct burning.

It's just that it is often mentioned in these forums that the "power kW" indicated can not be trusted on low power, and I want to know why.

Fordi der er unøjagtigheder der skal kompenseres for.

IF (a) the "power kW" reading works as I expect ( det gør det ikke ) and describe above, then the issue is that other people expect other things from it, and I'm still satisfied.

IF (b) it somehow by guessworking tries to show something else, then that's OK too, I'll just ignore the reading ( brug iltstyring og flowmåling, så er udlæsningen korrekt )from now on as it tells me nothing. I can still calculate it myself from the feeder-screw run time.

But which one is it? A or B?

[motoz]

Thanks, I'll ignore it then.

I have a lambda-sensor, but that cannot measure the burner efficiency. It can only help to keep it from changing after setup so I don't see how that changes anything.

Measuring water flow would be very expensive since I have three separate circuits from my boiler, and that would still not translate to how much pellet is fed to the burner when the burner/boiler efficiency is unknown.

I guess I can calculate and plot power from the pellet feeder time myself then I'll see for myself how the burner calculated value (whatever it calculates?) deviates from that.