Alarm in Sestos PID

[Tyr]

Hi there, I use a self build PID system to control a 25L electric kettle. It has been a long time since I use it and I think it is realible but there is a thing that is now missing and gets my nut off. I use a Sestos d1s-vr-220 PID and I want to set an alarm so that it can inform me when a fixed temperature is reached in the kettle. I wired the PID with a 220V buzzer like this:

Line (brown) and neutral (blue) are both controlled by an ON-OFF bipolar switch, neutral is then wired directly to the alarm whereas line is wired to 12 PID pin, as follow:

11 PID pin is then wired to the alarm. Is this system correctly wired?
Then, I need to set the PID alarm up but I don't understand how to do, accordingly to the following manual user: http://www.sestos-hk.com/english/download/d1s-en.pdf.
Is there someone so kind to explain me how to do in order to set the alarm up and be informed by the system when a certain temperature is reached in the kettle during the mash?
I thank you and look forward to hearing from you.
See you soon and have a great homebrewing time

Tyr

 

[doug293cz]

Alarm wiring sounds correct.

To set the alarm:

1. Press and hold "Set" button for ~2 sec. Display should read: "HIAL" & "9999"
2. Use down arrow button to reduce "9999" to the temp you want the alarm to trigger
3. Wait ~10 sec for unit to return to operation mode

​

Brew on

 

[Tyr]

Hi mate, thank you so much for your reply.
So it was so easy. Should I set other parameters, such as oP1 and ALP? How should I interpret Alarm Function Table (T1)?
I thank you and look forward to hearing from you.
Have a great homebrewing time.

Tyr

An OT question: how can I edit my posts?

 

[doug293cz]

I wouldn't set any other parameters unless you have a specific reason for changing them from the default. The defaults give you a pretty good place to start, and keep functions you aren't using (yet) from kicking in unexpectedly.

A couple that you might want to check are "Sn" to make sure it matches your temperature sensor type. Default is for a Type K thermocouple. If you are using something else (like a PT100 RTD) then "Sn" would need to be changed to match. The other is "Ctl" which is the PWM control period. At 4 seconds (the default) you might see visible pulsing during the boil. Reducing "Ctl" to 1 - 2 would give a more even boil.

The Alarm Function Table is a bit confusing to me (and there is no explanation given.) The settings for "ALP" other than "0" appear to control what alarm conditions will affect alarm relay #2, but there is only one alarm relay. Alarm relay #1 gets activated by all of the possible alarm conditions, but the default trigger limits for the conditions effectively prevent them from ever being triggered. That's why you have to set the High Temp Limit trigger ("HIAL") to the value that you want to trigger the alarm.

Brew on

 

[Tyr]

Thank you for your reply my friend!
I changed the K probe with a PT100 one and so I manually fixed the Sn parameter. Others changed due to Autotune and have been fixed accordinly to characteristics of my homemade BIAB plant. No other parameter has been changed but CtrL (PID), CF (Heating) and run (Automatic).
I wasn't aware of Ctl parameter but I don't use PID in boiling: I prefer to bypass it and make the kettle work at maximum power so that boiling is very impressive and vigorous with a modified lid (with a door kept opened so that it steams out).
Next time I will set HIAL parameter and test the buzzer. So I can set 64°C and the alarm will start ringing when that temperature is reached in the kettle, isn't it? ALP should be 0 because there are no reasons to modify it...

PS I found the edit button on my own...

Tyr

 

[doug293cz]

Yes, your HIAL setting should cause the alarm to buzz when the temp gets to 64.

There is a school of thought that believes boiling at more than a simmer is harmful to the wort (ref1 ref2). The rate of hop acid isomerization and conversion of SMM to DMS (which then evaporates) are both a function of temperature, not amount of heat input to the kettle. No matter how much heat you put into the kettle, you can't get the temp above 100°C. More heat input just means more boil off volume, and more heat damage to the wort.

Brew on

 

[Tyr]

Wow, I wasn't aware of, thank you. Which is your experience accordingly to this school of thought?
In order to simmer the wort, which option would be better in your opinion?

1. Bypass the PID, set the kettle to a medium-high power (not max level) and gradually reach the simmer (extending brewing times)
2. Bypass the PID and rapidly reach the simmer temperature at maximum power, then reduce to a lower power level and keep on simmering
3. Set Ctl to 1-2 and use PID to reach simmer, in this case, which temperature would be better to set?
4. Any other suggestion...

I thank you and look forward to hearing from you

Tyr

 

[doug293cz]

Set the PID temp target to 98°C. The when the wort reaches that temp, change to manual mode and set the power level to a value that gives you a simmer to gently rolling boil.

Brew on

 

[Tyr]

Thank you for tips!