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Lelit PL 92 T Elizabeth

@Konstantin

I refered to the preinfusion water flow...
PL92 is not only a thermal stable Dual Boiler espresso machine but also a chance to introduce people with  "low budget" in the world of espresso profiling, beginning with the first chapter - the preinfusion.

The main subject last week was the special feature of PL92 to wet the coffee puck in the preinfusion phase, at the steam boiler pressure, with the pump stopped. The measurements confirm that more you raise the steam boiler temp, more the preinfusion water flow raises up. And vice versa.

120 Celsius  => 6.75 ml/sec
135 Celsius  => 8.7 ml/sec
145 Celsius => 10.4 ml/sec

With Bianca in my head & blood, I supposed that If we find a trick to lower the steam boiler temperature at 115 Celsius degrees (for instance), the water flow in preinfusion will decrease more, maybe at 4ml/s, we don't know... From your experience with PL92, there is any way to modify this machine in order to lower the steam boiler temperature below 120 degrees (minimum set by factory) ? 
My target is to test a very slow preinfusion with PL92, at the minimum flow rate possible.
Lelit Bianca, Honne Slim ~ In vacanta: Kinu + Kompresso
Past: Expobar Brewtus IV, Mahlkonig Vario K30 
 
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(05-03-2019, 15:57)cradun Wrote: Hey, Konstantin, thank you for your kind replies on my quesions on your youtube channel.

Do you think, maybe, the exceptional thermal stability (flat temp profile) could be caused more by the preheating boiler than the PID's intervention?

Hello!
Exclusively due to the fact that the group is part of the boiler and the operation of the PID. I set the preheating, because I was wondering, the preheating of the coffee machine has little effect on the thermal stability of the coffee machine.
In addition, my video was recorded without installing pre-heating.

(05-03-2019, 16:27)Lyvyoo Wrote: @Konstantin

I refered to the preinfusion water flow...
PL92 is not only a thermal stable Dual Boiler espresso machine but also a chance to introduce people with  "low budget" in the world of espresso profiling, beginning with the first chapter - the preinfusion....

Now I understand, thanks!
It is very interesting.
Unfortunately, I did not conduct similar experiments, but I think that if you set the value of Es = 0 instead of Es = 5, the temperature of the steam boiler will decrease and the flow rate will decrease.
Lelit Elizabeth, La Pavoni Europiccola
Mazzer Kony, BlackJack 68mm
 
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@Konstantin just for clarity, have you added some sort of passive pre-heating, like a copper pipe, to your machine or are you refering to PID manipulation as pre-heating? Or maybe preheating is what happens during preinfusion?
factory g106, m47, ims, kazak accessories, fluid bed roaster
 
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(05-03-2019, 17:25)dev Wrote: @Konstantin just for clarity, have you added some sort of passive pre-heating, like a copper pipe, to your machine or are you refering to PID manipulation as pre-heating? Or maybe preheating is what happens during preinfusion?

In this video, the car is new, from the factory:



Now I have a pre-heated coffee boiler (copper tube), but this does not increase the thermal stability of the coffee machine. I just wanted to install it.
The design of the group and PID, provide absolute temperature stability of the coffee machine, it does not require modifications.

[Image: 25649729.jpg]

Made a new video with other PID settings:
Lelit Elizabeth, La Pavoni Europiccola
Mazzer Kony, BlackJack 68mm
 
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I understand, with the copper coil you eliminated the need for preinfusion from the steam boiler that also added to the thermal stability.

The colleagues were discussing about what would be the minimal steam boiler temperature in order to achieve a very slow flow preinfusion. I guess 120 is the lowest available setting.
factory g106, m47, ims, kazak accessories, fluid bed roaster
 
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(05-03-2019, 15:24)Konstantin Wrote: The fact is that I have a pre-heating boiler installed, so my settings may not be accurate. Here are my settings:
KPc 4.0
Klc 0.0
KDc 10.0
Just for reference, default PID settings are KPc=20 KIc=0 KDc=20. The large value for KPc and the missing KIc component are inducing an oscillatory regimen of the boiler temp, with the same type of hysteresis that we would get from a cheap thermostat. It may not affect your setup that much since you added that copper coil which increases thermal mass and inertia, but on a stock machine these default settings are quite bad.

Also, what kind of temp. sensor are you using? RTD? Thermocouple?
 
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(05-03-2019, 23:25)andrei_0 Wrote:
(05-03-2019, 15:24)Konstantin Wrote: The fact is that I have a pre-heating boiler installed, so my settings may not be accurate. Here are my settings:
KPc 4.0
Klc 0.0
KDc 10.0
Just for reference, default PID settings are KPc=20 KIc=0 KDc=20. The large value for KPc and the missing KIc component are inducing an oscillatory regimen of the boiler temp, with the same type of hysteresis that we would get from a cheap thermostat. It may not affect your setup that much since you added that copper coil which increases thermal mass and inertia, but on a stock machine these default settings are quite bad.

Also, what kind of temp. sensor are you using? RTD? Thermocouple?   

You're right.
KPc is the pulse duration, KDc is the pulse frequency.
With standard values of KPc = 20 and KDc = 20, the inertia is too large.
Yesterday I experimented with the settings and stopped at KPc = 2 and KDc = 7.

I use only industrial equipment with relevant certificates, I do not use Chinese thermometers and sensors.
At first I used a platinum sensor, Pt100 thermistors, but its inertia is too large and the reaction time is low, the measurements are not accurate.
So now I use a thermocouple, also an industrial one.

(05-03-2019, 22:17)dev Wrote: I understand, with the copper coil you eliminated the need for preinfusion from the steam boiler that also added to the thermal stability.

The colleagues were discussing about what would be the minimal steam boiler temperature in order to achieve a very slow flow preinfusion. I guess 120 is the lowest available setting.

I agree with you, I think, thanks to the copper coil, I received some stabilization of the temperature.
Regarding flow control, is it not easier to install a dimmer on the pump.
Lelit Elizabeth, La Pavoni Europiccola
Mazzer Kony, BlackJack 68mm
 
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(06-03-2019, 05:46)Konstantin Wrote:
(05-03-2019, 23:25)andrei_0 Wrote:
(05-03-2019, 15:24)Konstantin Wrote: The fact is that I have a pre-heating boiler installed, so my settings may not be accurate. Here are my settings:
KPc 4.0
Klc 0.0
KDc 10.0
Just for reference, default PID settings are KPc=20 KIc=0 KDc=20. The large value for KPc and the missing KIc component are inducing an oscillatory regimen of the boiler temp, with the same type of hysteresis that we would get from a cheap thermostat. It may not affect your setup that much since you added that copper coil which increases thermal mass and inertia, but on a stock machine these default settings are quite bad.

Also, what kind of temp. sensor are you using? RTD? Thermocouple?    

You're right.
KPc is the pulse duration, KDc is the pulse frequency.
With standard values of KPc = 20 and KDc = 20, the inertia is too large.
Yesterday I experimented with the settings and stopped at KPc = 2 and KDc = 7.

I use only industrial equipment with relevant certificates, I do not use Chinese thermometers and sensors.
At first I used a platinum sensor, Pt100 thermistors, but its inertia is too large and the reaction time is low, the measurements are not accurate.
So now I use a thermocouple, also an industrial one.

(05-03-2019, 22:17)dev Wrote: I understand, with the copper coil you eliminated the need for preinfusion from the steam boiler that also added to the thermal stability.

The colleagues were discussing about what would be the minimal steam boiler temperature in order to achieve a very slow flow preinfusion. I guess 120 is the lowest available setting.

I agree with you, I think, thanks to the copper coil, I received some stabilization of the temperature.
Regarding flow control, is it not easier to install a dimmer on the pump. 

Konstatin, you mentioned a dimmer; what about  one with PWM (pulse width modulation), not the common ones used for dimming lights let's say? Those should provide full flow control.
QuickMill QM67,  MK E65S, tamper si distribuidor Bravo
 
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You need a different pump because the stock ULKA pump doesn't like dimming that much. ARS CP3 is the best dimmable pump.
factory g106, m47, ims, kazak accessories, fluid bed roaster
 
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(06-03-2019, 05:46)Konstantin Wrote: You're right.
KPc is the pulse duration, KDc is the pulse frequency.
That's not quite how a PID works, KP is the "proportional" factor and KD is the "derivative" factor from the PID control loop. But anyways, let's not get carried away with these details.

(06-03-2019, 05:46)Konstantin Wrote: With standard values of KPc = 20 and KDc = 20, the inertia is too large.
Yesterday I experimented with the settings and stopped at KPc = 2 and KDc = 7.
Although better than the original, I'm pretty sure these parameters lead to an unstable loop on a standard machine. There are several algorithms for tuning a PID controller, I applied one such method and got the following settings: KPc = 0.7, KIc = 0.03, KDc=15. A huge difference from the original values, but with these the PID is quite stable and has a fast recovery.
 
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@Konstantin

What did you set for the coffee offset value(Ec) so dat you get the proper temperature in you portafilter. Factory i got 10 and I suspect that it's to high.
Echipament actual:Lelit PL92T, Niche Zero
Echipamentul vechi: Lelit PL81T, Gaggia Baby, Saeco Poemia cu PF naked facut la strung, Kinu M47, Lelit PL043MMI, Hario Skerton 
 
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Am o intrebare pentru posesorii espressorului: Cum iese frotarea daca scadeti temperatura din boilerul de aburi? Am vazut filmulete cu o crema excelenta dar era la 135 grade cred(asa vine din fabrica?). 

Sau: daca pastram temperatura la 135 grade, cat de tare mai influenteaza(pozitiv) preinfuzia gustul din ceasca, tinand cont ca se face la presiune mai mare?
Lelit PL62S, Mazzer Major
Ex: Gaggia Classic, Vario
 
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Ori abur puternic, ori preinfuzie lunga. Dar e simplu de schimbat temperatura, eu beau de obicei espresso si o tin la 120. Cand fac spuma, o cresc.
 
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Salut!

De ieri am întrat și eu în clubul celor cu Elizabeth. Din fabrica trimit aparatul, în continuare, cu aceleași setări proaste ale PID-ului dar după ce le-am modificat, conform cu valorile date de Andrei, acum temperatura nu mai oscilează asa mult pana sa ajungă la valoarea setata
(15-03-2019, 12:13)lorisl Wrote: @Konstantin

What did you set for the coffee offset value(Ec) so dat you get the proper temperature in you portafilter. Factory i got 10 and I suspect that it's to high.
Voi cum aveți setat offsetul căci și mie mi se pare cam mare 10 cu cât a venit din fabrica? Era bine dacă @Konstantin ne-ar fi zis exact cât are el pe aparat..

Sent from my SM-G960F using Tapatalk
Lelit PL92 + Kinu M47 & Gaggia Classic 2019 + Kinu M47
 
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din raspunsul lui @Konstantin cu setarile PID-ului, vad el are Ec=15 ceea e chiar mult  (temperatura apei, unde e senzorul, ar trebui sa fie in jur de 110 grade). 

La mine, dupa ce am pus setarile date de @andrei_0, am urmatorul comportament: in primele 5 minute temperatura ajunge la 94 de grade dar, dupa inca 5 minute, ea urca pana la 120 si de acolo incepe sa scada pana la valoarea setata. Tot acest proces dureaza 15 minute si nu  m-am jucat inca cu valorile PID-ului deoarece oricum il las minim 15 minute sa se incalzeasca. Totusi, mi se pare anormal sa creasca asa mult temperatura peste valoarea setata. La voi cat dureaza pana se stabilizeaza?
Lelit PL92 + Kinu M47 & Gaggia Classic 2019 + Kinu M47
 
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Dupa ce am modificat setarile am sesizat acelasi comportament. Temperatura ajunge undeva in zona 120 grade si de acolo incepe sa scada pana la 94. Pentru a se stabiliza cred ca ii ia undeva la 20-25 minute(de cand il pornesc).
PL92T, KG79
 
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Asa este setat si pe Bianca, s-a discutat... Dar in cazul E61 chiar "face sens mai mult" pentru ca in general, grupurile E61 au nevoie de 30-40 min pentru a fi stabilizate. Ca majoritatea aparatelor bune, in general. In regimul acesta nou gandit de Lelit, de grabire a incalzirii prin ajungerea apei la 120 de grade si apoi stabilizarea usoara spre temperatura dorita, am observat ca pot face un espresso fara nuante acrisoare nedorite inclusiv in cazurile cand ma grabesc al naibii de tare si nu pot astepta 30-40min. , lucru care pe fostul DB cu E61 sau pe alte DB-uri cu E61 pe care le-am mai testat in diverse ocazii, nu se putea. Si ma refer la timpi de incalzire de 20-25 de minute.
Lelit Bianca, Honne Slim ~ In vacanta: Kinu + Kompresso
Past: Expobar Brewtus IV, Mahlkonig Vario K30 
 
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Nu cred ca e "gandit" de Lelit, e o consecinta a mai multor factori ce tin de constructia masinii si pozitionarea sondei de temperatura combinat cu setarile PID-ului. Eu am cautat un set de parametri care ofera viteza de incalzire si stabilitate dupa ce se ajunge la echilibrul termic. Pe cine deranjeaza faptul ca in primele minute temperatura sare destul de mult de valoarea setata poate experimenta cu un set de parametri ce duc la o curba de incalzire mai lenta. Sau daca va grabiti, puteti face un flush...
 
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Am zis "gandit" pt ca la fel e si pe Bianca, iar PL92 s-a lansat aproximativ in aceeași perioadă... Pare ceva intentionat, ca răspuns la cererile repetate ale utilizatorilor , in general, de incalzire mai rapida a aparatelor. Asta nu insramna ca nu trebuie sa recomandam in continuare rabdarea ...
Lelit Bianca, Honne Slim ~ In vacanta: Kinu + Kompresso
Past: Expobar Brewtus IV, Mahlkonig Vario K30 
 
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Salut,

de azi am intrat in posesia unui Lelit PL92T. Am remarcat pe forum ca Lelit nu ar furniza chiar cea mai buna sita. V-as ruga sa-mi recomandati o sita buna si de unde o pot achizitiona.

multumesc

(22-02-2019, 15:29)lorisl Wrote: Bun, azi a sosit. Cutia avea o gaura mare in ea, cei de la nemo nu au fost prea atenti. Din fericire am luat rapid legatura cu cei de la silmar, am trimis poze, au zis sa deschid si sa verific daca e afectat cumva aparatul, pe scurt nu e afectat. Asta ca si o paranteza.

Masinaria. E mult mai ok decat ma asteptat. Eu sincer credeam ca e un PL81T cu 2 boilere, grup de 58, preinfuzie programabila pe secunde si smecheria cu boilerul de aburi care preincazleste apa si face preinfuzie.

E mai mult de atat.

Grupul e total diferit fata de 81T, sita de dus de la 81T nu potriveste aici. E o sita care seamana cu aceasta .Diseara o si masor. Sub sita e o bucata mare de alama?? care din pacate era putin murdara si nu am reusit sa o curat(daca aveti sugestii cum as putea sa o curat, va ascult). Aceasta bucata de metal cred ca are 2 roluri, a) ajuta la o mai buna distributie a apei datorita gaurilor, b) ofera stablitate termica mai buna. Corectati-ma daca vorbesc prostii

Teava de abur e cu 2 gauri, no burn. Dar ce mi-a placut cel mai mult e potentiometrul de abur. Cu o rotire de aprox 270 de grade deschizi complet robinetul de aburi. La 81T dadeam peste 2 ture.

Cu preinfuzia trebuie sa ma joc mai mult. Ca si prima impresie, cand vezi cum curge crema aia la preinfuzie te si unge pe suflet. Inca nu stiu cum sa imi calculez timpul de brew. Adica, daca am preinfuzie 10 secunde, mai adaug 25-30 de secunde pana ajung la ratie 1:2? Sau sa tintesc 25-30 de secunde cu tot cu preinfuzia?

De stabilitate termina nu pot sa zic nimic, nu am scule sa o masor.

Ca si minus, vine cu aceeasi sita de foarte proasta calitate ca si 81T si cam toate leliturile(presupun ca la bianca e totusi alta sita). Eram pregatit si aveam comandata o sita ims. Tamperul care vin la oferta cu espressorul e prea mic, voi comanda unul de 58.4, 58.5.


@Lyvyoo astept niste instructiuni/sfaturi pentru o modalitate de a masura debitul la preinfuzie.

[Image: y0KyoIp.jpg][Image: 7EQN2oE.jpg]

salut!

cu ce sita ai inlocuit-o pe cea originala? Daca poti te rog trimite-mi un link.

Multumesc mult!
 
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