Commencing Final Dream Temperature Tests

Forums below are for discussions of Dream and Dream T specific issues. However, both machines have as much, if not more, in common than they have differences. This area is for information sharing and questions that you think apply equally to both machines.
Post Reply
User avatar
chas
Vivaldi Dreamer
Posts: 3044
Joined: Wed Jun 02, 2004 11:52 pm
Location: Central Maryland
Contact:

Commencing Final Dream Temperature Tests

Post by chas »

Now that the Dream machines are in very good and stable configuration with the Dream 1.19 software it is time for one more final pass at temperature testing. I have long overstayed my loan of the 53mm Scace device I plan to complete testing as early as tomorrow and then return the device.

I had previously changed my PID settings to an equivalent value to what I use on my GS/3 and it works very well - much better than the Dream defaults. Today, I returned the PID settings to the default value P=500, I=150, D=10,000 and retested to see if the result was any different with the 1.19 SW compared to earlier versions. It wasn't. I still see a large overshoot, then the temperature settles a bit below the setpoint.

I am now testing some values more similar to the GS/3 settings to see if I can find a set of values that are even better. I'll let you know what I have finally settled on for my permanent settings.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
User avatar
chas
Vivaldi Dreamer
Posts: 3044
Joined: Wed Jun 02, 2004 11:52 pm
Location: Central Maryland
Contact:

Re: Commencing Final Dream Temperature Tests

Post by chas »

After a lot of testing, the final values I'm sticking with are:
P=800
I=15
D=1000
Offset = 0F
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
goodboyr
Barista
Posts: 255
Joined: Thu Jan 10, 2013 10:05 pm
Location: Canada

Re: Commencing Final Dream Temperature Tests

Post by goodboyr »

Chas: I assume this would be applicable to all Dream owners. Are there any consideration that we should be worried about before we try these?

Sent from my SGH-I747M using Tapatalk 4 Beta
Bob
La Spaziale Dream and Baratza Sette 270W
User avatar
chas
Vivaldi Dreamer
Posts: 3044
Joined: Wed Jun 02, 2004 11:52 pm
Location: Central Maryland
Contact:

Re: Commencing Final Dream Temperature Tests

Post by chas »

If you haven't already done so:

1) Be sure the offset is set to 0F
2) Upgrade to SW v1.19
3) Change PID settings

One thing LaSpaz did in version 1.19 at my request is to implement the hold down button for fast scroll option to the Offset and PID settings. You will definitely need it especially when you have to change the D setting from 10,000 to 1,000. However, there seems to be a bug in it. If you hold down the button the value starts to increment or decrement by 1. After a few seconds it starts changing by 10s. However, within a few more seconds the increment/decrement stops and you have to take your finger off the button for 1-2 s and then press and start all over with the slow increment by 1. So while it is a still a lot faster than pressing the down arrow 9,000 times, it takes longer than it should due to this bug. Sometimes the machine would stop and beep at the same time. Other times it would stop and not beep. Let me know if the same thing happens when you try it. If so, I'll write it up and forward to CCS to add to the bug list for the next go around.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
goodboyr
Barista
Posts: 255
Joined: Thu Jan 10, 2013 10:05 pm
Location: Canada

Re: Commencing Final Dream Temperature Tests

Post by goodboyr »

Another alternative is to directly edit the settings file and use the Write/Read feature. I will give that a try tonight.
Bob
La Spaziale Dream and Baratza Sette 270W
User avatar
chas
Vivaldi Dreamer
Posts: 3044
Joined: Wed Jun 02, 2004 11:52 pm
Location: Central Maryland
Contact:

Re: Commencing Final Dream Temperature Tests

Post by chas »

That's works too. Just remember to correct your time and date after you do so since the original time and date from when you saved the file will get written back to the machine.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
goodboyr
Barista
Posts: 255
Joined: Thu Jan 10, 2013 10:05 pm
Location: Canada

Re: Commencing Final Dream Temperature Tests

Post by goodboyr »

I confirm that the buttons behave the way you describe. It just seems to stop scrolling fairly randomly

Sent from my SGH-I747M using Tapatalk 4 Beta
Bob
La Spaziale Dream and Baratza Sette 270W
goodboyr
Barista
Posts: 255
Joined: Thu Jan 10, 2013 10:05 pm
Location: Canada

Re: Commencing Final Dream Temperature Tests

Post by goodboyr »

Question on how the displayed temperature changes during and after a warming pull with the new PID settings vs the old ones. With the new settings and a 10 second pull through an empty pf, with a setpoint of 199 F, the temperature drops to 189 during the pull, then after the pull rapidly recovers and then overshoots to 205 before settling back to setpoint. With original PID settings there was the same temperature drop during the pull, but there was little or no overshoot after. Chas: Is this what you see on yours? I'm just trying to confirm that the new PID settings are right for my machine.

Sent from my SGH-I747M using Tapatalk 4 Beta
Bob
La Spaziale Dream and Baratza Sette 270W
goodboyr
Barista
Posts: 255
Joined: Thu Jan 10, 2013 10:05 pm
Location: Canada

Re: Commencing Final Dream Temperature Tests

Post by goodboyr »

Bump for my question above. Thxs.

Sent from my SGH-I747M using Tapatalk 4 Beta
Bob
La Spaziale Dream and Baratza Sette 270W
User avatar
chas
Vivaldi Dreamer
Posts: 3044
Joined: Wed Jun 02, 2004 11:52 pm
Location: Central Maryland
Contact:

Re: Commencing Final Dream Temperature Tests

Post by chas »

Without a Scace device or something very similar, it's very difficult to do any kind of apples to apples comparison.

First, the stability of the group boiler is dependent by design on having the flow rate be in the general range of no more than 2oz in 25sec. A little slower is probably OK but a faster flow rate will let cold water into the boiler faster than the boiler can heat it. So if you are just looking at the boiler temperature display and running water through the group without any kind of flow restrictor the temperature display is meaningless.

Frankly, when you reset the PID settings to the new ones I am using, the display temperature settings are also meaningless even when the flow rate is in the correct range. This is because the temperature probe is screwed into the top, rear of the boiler not all that far from where the cold water enters and the group where we want a specific water temperature to be stable is diagonally opposite from the temperature probe and about as far away as possible.

To try to get to the point, if you use the PID settings I am using and set the temp to 199F and the offset to 0F, you should get a pretty flat stable 199F at the group after 1-2 warm up flushes. The temperature may fluctuate around as to what the temperature probe says but it doesn't really matter what the water temperature is at that spot in the boiler, it matters only at the top of the coffee bed.

If you use the original PID settings, the display temperature will match more closely to the set temperature but won't necessarily correlate well to the actual temperature at the coffee and you may need a +2F offset.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
goodboyr
Barista
Posts: 255
Joined: Thu Jan 10, 2013 10:05 pm
Location: Canada

Re: Commencing Final Dream Temperature Tests

Post by goodboyr »

Chas: Thanks for that explanation. I guess it all has to do with taste, and despite the wandering temp display, the shots are great with the new settings. One additional question: The overshoot on my temperature display results in a bigger than normal delay in the next shot if I am pulling back to back, because I am waiting till the display returns to setpoint after the overshoot. I think your explanation tells me that I don't need to wait. As long as the wavy line is off, it means the brew boiler has returned to short range PID control. When you did your scace tests, did you wait until the temperature display returned to the setpoint after the overshoot, or did you just wait until the wavy line went off?
Last edited by goodboyr on Wed Jun 19, 2013 12:42 pm, edited 1 time in total.
Bob
La Spaziale Dream and Baratza Sette 270W
User avatar
chas
Vivaldi Dreamer
Posts: 3044
Joined: Wed Jun 02, 2004 11:52 pm
Location: Central Maryland
Contact:

Re: Commencing Final Dream Temperature Tests

Post by chas »

Yes, I go by the wavy line turning off. That reminds me of one other test I want to make soon. I am wondering just how accurate the wavy line is. I also have a PID'd GS/3 and it just has two side-by-side black boxes that turn on and off when the steam and group boilers are cycling. On that machine every few seconds one or the other or both turns on just for a second or two indicating a frequent pulsing to keep the temperature right on target. This seems to me like the way a PID'd machine should work.

However, if I look at when the wavy line turns on and off on the Dream it is pretty much the exact same on-off pattern and times as the older generation of non-PID'd S1 machines. So what I want to do is connect an AC voltmeter across the boiler element on the Dream (or maybe even an oscilloscope if I need a faster response time) so I can see if the boiler's real on/off cycles at all match the wavy line.

Several SW versions ago there was a bug where if you set the Dream to the max offset the wavy line turned on and stayed on. However, I did not get any indication of expected overheating when it was in that condition so I connected an AC voltmeter and the voltage seemed to be pulsing like it does on the GS/3. I have not gotten back to recheck this with the newer SW versions, but I must!
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
Owen
Freeze Dried
Posts: 4
Joined: Mon Oct 26, 2020 7:39 pm
Location: Lubbock, TX

Re: Commencing Final Dream Temperature Tests

Post by Owen »

Chas,

I instituted your PID suggestions below:

"After a lot of testing, the final values I'm sticking with are:
P=800
I=15
D=1000
Offset = 0F"

Has anything changed after 7 years? I know you referenced SW 1.19, and I am on 1.24 now. Would this matter? Are the factory settings in the latest SW any better than what was in 1.19?

Thanks for the refresh!
Velcro
Macchiato
Posts: 46
Joined: Tue Mar 06, 2018 5:28 pm
Location: PA

Re: Commencing Final Dream Temperature Tests

Post by Velcro »

I never looked at my PID settings, perhaps I shouldn't have but now Pandora's box is open....
My Dream's unmodified settings (default?) for SW 1.24 are
P = 300
I = 100
D = 10,000
Offset = 0F

Should I change to ?
P = 800
I = 15
D = 1000

The manual shows
P = 800
I = 150
D = 1000
but states the default is
P = 300
I = 1000
D = 10,000

So this all gets very confusing....
What should I be using?
thanks
Velcro
Sette 270
La Spaziale Dream v1.24
IMS Baskets & Reg Barber C-Flat 53.3
User avatar
chas
Vivaldi Dreamer
Posts: 3044
Joined: Wed Jun 02, 2004 11:52 pm
Location: Central Maryland
Contact:

Re: Commencing Final Dream Temperature Tests

Post by chas »

The alternate values are the ones I used after a wide range of testing. Feel free to use them, stick with the defaults if you are happy with the performance, or try other values. I used a Scace device with a recording digital thermometer for my testing. If you don't have something equivalent and/or don't feel confident to fiddle with the PID settings, leave them alone.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
Velcro
Macchiato
Posts: 46
Joined: Tue Mar 06, 2018 5:28 pm
Location: PA

Re: Commencing Final Dream Temperature Tests

Post by Velcro »

thanks chas. merry xmas.
its good to know your still using those settings.
I have been playing with your PID settings the last few days and have a few questions.

With P=800 I=15 D=1000, when I pull a shot with my temp set to 200F I see the temp drop to ~190F and then rise to ~205F during the shot and overshoot to 208F after the shot finished. It then settles back down to 200F (temps are from my Dream's display not a Scace so I know its not ideal). I see the same overshoot to 208F with warming shots too.
Is this what you see on your display too? expected?

Am I correct in assuming that after warming shots reheat to 208F you wait for the temp to cool back to your setpoint (ie 200F in this case) to pull you espresso?
lastly do you pull your warming shots at the setpoint (200F) or at the high of the over shoot (208F) or some other point?

playing with this has been very interesting as its taken some of the sour out of my shots :grin:
thanks again
Velcro
Sette 270
La Spaziale Dream v1.24
IMS Baskets & Reg Barber C-Flat 53.3
User avatar
chas
Vivaldi Dreamer
Posts: 3044
Joined: Wed Jun 02, 2004 11:52 pm
Location: Central Maryland
Contact:

Re: Commencing Final Dream Temperature Tests

Post by chas »

How are you testing? The boiler temp isn't a good indicator of the temp of the water at the top of the puck. I used a Scace device for my testing.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
Velcro
Macchiato
Posts: 46
Joined: Tue Mar 06, 2018 5:28 pm
Location: PA

Re: Commencing Final Dream Temperature Tests

Post by Velcro »

Sry Chas didn't get notified you had responded and then was away.
I know the temp on the display panel is not accurate for this but its all I have now. I don't have easy access to a scarce.
I trust your settings - I was just curious if you saw similar fluctuation on your display panel to confirm my machine was responding similarly to yours. I was also curious how the higher boiler temp overshoot might work in favor of warming the up the cold nose group head?
Hope what I'm asking was clear and makes sense.
Thanks
Velcro
Sette 270
La Spaziale Dream v1.24
IMS Baskets & Reg Barber C-Flat 53.3
User avatar
chas
Vivaldi Dreamer
Posts: 3044
Joined: Wed Jun 02, 2004 11:52 pm
Location: Central Maryland
Contact:

Re: Commencing Final Dream Temperature Tests

Post by chas »

I've attached a PDF file that contains plots I made of several back-to-back shots using the Scace device and a recording Digital Thermometer. As you can see you still need to start with a couple of warming shots to get past the "cold nose" effect. After that, the shot temperature is pretty flat for the period that a shot is being pulled. The final graphed shot I let go for well over a minute to see what would happen. The temperature starts to rise at the one-minute mark which is well past the time you would pull a shot. It remains flat during the shot pull time.

I did not pay any attention to the built-in temperature gauge since I didn't really care about the temperature in the middle of the boiler.
DreamP-800I-15D-1000.pdf
(76.83 KiB) Downloaded 189 times
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
Velcro
Macchiato
Posts: 46
Joined: Tue Mar 06, 2018 5:28 pm
Location: PA

Re: Commencing Final Dream Temperature Tests

Post by Velcro »

thanks for the charts
it looks like your setpoint temp was 201F? is that correct?
the chart rise over "very long" pulls kind of fits with what I see from the boiler panel temp rising over the pull.
If would be helpful if you knew how your display panel temps changed but that's ok. the end result is what's in the cup and I think its improved with your settings.

thanks
Velcro
Sette 270
La Spaziale Dream v1.24
IMS Baskets & Reg Barber C-Flat 53.3
Post Reply

Return to “Dream and Dream T Common Feature Discussions”