ACS Vesuvius Evo Leva - Consecutive shots and long shots - Page 5

A haven dedicated to manual espresso machine aficionados.
bakafish

#41: Post by bakafish »

pizzaman383 wrote:A thin-wire thermocouple will react faster.
Yes, I used thin-wire thermocouple, not ultra thin though, but react fast enough.

Paolo

#42: Post by Paolo »

bakafish wrote:
In addition, there is an interesting thing. Due to the 2 150W cartridge heaters are too weak, or without a dedicated PID for the grouphead, the grouphead temperature showed on the PID is always 1C to 2C lower than the setting (If I set it 98C, it can reach 96C to 97C, but never 98C). The grouphead temperature that I mentioned previously are the readings showed on the PID, not the setting (For example, when I said the setting is 96C, the reading on the PID is 96, and the setting is 97). The heaters are weak so they cannot heat the water quickly. It must be the grouphead which is hotter than the water. Anyway, it is the situation of my Nurri Leva. If you choose other machine, or the Nurri Leva has some improvements, it would be different.

Hi there,
Just wondering if you have looked into whether more powerful heater cartridges are available to suit? If so, would the power consumption of the machine be too much for the electicity mains circuit to handle safely?

What settings (group and water temp) do you use for most of your shots with the Nurri?

Cuprajake

#43: Post by Cuprajake »

I may take a vid showing how quick the temp drops on the group when the heaters are off

bakafish

#44: Post by bakafish »

Paolo wrote: Hi there,
Just wondering if you have looked into whether more powerful heater cartridges are available to suit? If so, would the power consumption of the machine be too much for the electicity mains circuit to handle safely?

What settings (group and water temp) do you use for most of your shots with the Nurri?
ACS Evo seems to use 200W cartridge heaters. I don't know if they are interchangeable. Even the ACS Evo's cartridge heater can be installed in the Nurri Leva grouphead, I don't know if I can use it without changing the control box or PID. In Taiwan the safe current for a circuit is 15A. A 220V machine can be 3300W. Both boiler heaters of Nurri Leva are 1000W so there is not the safety issue.

I drink light to medium roasts most and prefer the coffee boiler 96C and the grouphead 95C (the setting, not the reading :D ).
I changed the PID parameters. If you prefer lower temperature, it would be better to use default parameters or the coffee boiler overshoots frequently.

The default parameters:
P=0.9
I=0.00
D=3.0

My parameters:
P=1.8
I=0.03
D=10

User avatar
Viernes

#45: Post by Viernes »

bakafish wrote:
The Nurri Leva has only 2 150W cartridge heaters in the grouphead, so the grouphead should have hotter and cooler spots. If the sensor is near the heater, when it measures 96C, the temperature of other parts far from the heaters is lower than 96C. But I don't know its real temperature, so I have to use some methods to test it. Of course there are some more accurate methods. For example, take out the shower screen, stop the pump, pull the lever, and measure the surface temperature from the inside of the grouphead chamber.

In addition, there is an interesting thing. Due to the 2 150W cartridge heaters are too weak, or without a dedicated PID for the grouphead, the grouphead temperature showed on the PID is always 1C to 2C lower than the setting (If I set it 98C, it can reach 96C to 97C, but never 98C). The grouphead temperature that I mentioned previously are the readings showed on the PID, not the setting (For example, when I said the setting is 96C, the reading on the PID is 96, and the setting is 97). The heaters are weak so they cannot heat the water quickly. It must be the grouphead which is hotter than the water. Anyway, it is the situation of my Nurri Leva. If you choose other machine, or the Nurri Leva has some improvements, it would be different.
If you set the heaters to 90C you will get a reading of 88-89C. If you set the heaters to 98C, you will get 96-97C as you said. Therefore that cannot be an issue of lack of power... otherwise, you could not reach those 97C

As far as I know, the EVO uses 2x110W, there are no problems of lack of power and the group is the same.

I measured the draw current of the LType, and the heaters draw 300W. Also, when group temperature is reached (for example, setting 90, reaching 88-89C) the PID does pulses to keep the temperature, instead of being turned on constantly to full power if the problem were lack power.

Anyway, I think the post is about the EVO. Excuse me for the off topic.

bakafish

#46: Post by bakafish »

Viernes wrote:If you set the heaters to 90C you will get a reading of 88-89C. If you set the heaters to 98C, you will get 96-97C as you said. Therefore that cannot be an issue of lack of power... otherwise, you could not reach those 97C
Maybe the root cause is no dedicated PID for the grouphead. Since Nurri designed to use only 1 PID, I thought could it be the combination of the non-dedicated PID and the heaters power is not enough and if it can be solved by not adding an additional PID.
Viernes wrote: I measured the draw current of the LType, and the heaters draw 300W. Also, when group temperature is reached (for example, setting 90, reaching 88-89C) the PID does pulses to keep the temperature, instead of being turned on constantly to full power if the problem were lack power.
I know this, but it cannot reach the setting. I don't know how the PID controls the power actually. I just thought if the PID uses some percentage of power with the same PID parameters at a certain temperature, the more powerful heaters mean more power used at this stage which can push the grouphead temperature to reach the setting.

Cuprajake

#47: Post by Cuprajake »

The nurri has less tech regards to temp stability than the Evo does.

User avatar
Viernes

#48: Post by Viernes replying to Cuprajake »

The PID processor is the same. The LType is going to get a software update to enable independent PID settings for each probe. It wasn't enabled to avoid overcomplexity in the temperature settings, but people have asked for it, so it's here.

Cuprajake

#49: Post by Cuprajake »

I thought the nurri had 2 pids Vs 3 in the evo