Hearts take-off

Samovar 7.00: when the impurity detector is enabled, a warning reduces the take-off rate, and a critical state pauses the process. After a manual resume, the automatic reaction is temporarily not applied for about a minute; repeated stop-pauses can lower the base rate of the current line.

 

When Samovar moves on to running the hearts take-off program, it remembers the temperatures of the vapor sensor and of the column section sensor. From then on, Samovar relies on these temperatures during operation. The fixed temperatures are shown in the status line on the main tab, and the message "New hearts T: vapor = …, section = …" («Новые Т тела: пар = …, царга = …») appears in the messages.

 

 

 

The setpoints are set on the "Settings" («Настройки») → "Temperature" («Температура») tab: "Vapor sensor overshoot before the dephlegmator" («Вылет за уставку датчика пара перед дефлегматором») and "Column section sensor overshoot at 2/3 of the column" («Вылет за уставку датчика в царге на 2/3 колонны») (°C), as well as "Take-off delay when vapor T exceeds the setpoint" («Задержка отбора при выходе Т пара за уставку») and "Take-off delay when section T exceeds the setpoint" («Задержка отбора при выходе Т в царге за уставку») (seconds). If the overshoot is 0, control by that sensor is disabled.

When the sensor temperature rises to the fixed one plus the setpoint, Samovar stops the pump, sounds a beep and shows the message "Pause by vapor T" («Пауза по Т пара») or "Pause by section T" («Пауза по Т царги»). The take-off resumes (message "Resuming take-off after automatic pause" («Продолжаем отбор после автоматической паузы»)) once the set delay has passed and the temperature has dropped below the threshold (with a 0.07° margin so the pause does not chatter at the boundary). If three such pauses (from the sensors or from the detector) pile up during one line, Samovar lowers the base rate of this line by 10% and reports it.

 

You can cancel pausing the take-off when temperatures exceed the setpoint: instead of pausing, Samovar fixes new hearts temperatures.

The take-off will not be paused provided that:

It is the first Hearts or Pre-flooding line after a Heads line ("Pause" lines between them do not count).
For example:

While running line no. 2, Samovar will not pause the take-off but will record new vapor and column section temperatures. While running lines no. 3 and no. 4, the take-off will be paused.

If a Pre-flooding line is anywhere in the take-off program and is followed by two Hearts or Pre-flooding lines in any combination (the first of them may also be a "Pause" line).

For example:

If temperatures exceed the setpoint while line no. 2 (the first hearts line after heads) and line no. 4 (pre-flooding followed by two more hearts lines) are running, Samovar will not pause the take-off but will remember the new vapor and column section temperatures. While running lines no. 5 and no. 6, the take-off will be paused if temperatures exceed the setpoint.

The automatic temperature rise is limited: within one line, Samovar raises them by no more than 0.3° from the first vapor temperature fixed in that line. Above this limit, exceeding the setpoint causes a normal pause.

 

The function is enabled in the Samovar_ini.h file. The line

In the standard build the function is enabled. You can disable it in the user_config_override.h file, and the rise limit is set by the line #define BODY_TEMP_AUTOSET_MAX_RISE 0.3f in Samovar_ini.h.

 

- If the "Use pressure correction" («Использовать корректировку давления») option was enabled in the settings, Samovar converts the temperature sensor readings to a pressure of 760 mm Hg using the pressure sensor. The fixed hearts take-off temperatures then do not depend on changes in atmospheric pressure during distillation: when the pressure drops, the actual boiling temperature falls, but the converted value stays in place, and there will be no false pause.

 

It is enabled in the settings with the "Use detector" («Использовать детектор») checkbox (without it the detector does not work at all). On Hearts and Pre-flooding lines the detector monitors the rate of temperature rise (°C/min) - using the vapor sensor, and when the boiler temperature is above 92.5°, using the column section sensor. The detector picks the trigger threshold itself, after measuring its own temperature noise during a calm period. The detector state is shown in the card on the main tab: "stable" («стабильно»), "rising" («рост») (or "reducing rate" («снижаю скорость»)), "breakthrough" («проскок»).

- When the rise is above the threshold (warning), if the "Reduce take-off rate when temperature rises" («Снижать скорость отбора при росте температуры») checkbox is enabled, Samovar reduces the take-off rate step by step by the "Rate reduction step" («Шаг снижения скорости») (5% by default, 20% maximum), but not below 70% of the line's base rate. When the rise stops, the rate returns to the base rate in the same step-by-step way. Without this checkbox the detector only reports the rise.

- On the first hearts line after heads, the detector warning fixes new hearts temperatures (within the same 0.3°) instead of reducing the rate.

- On a critical rise (2.5 times above the threshold, two measurements in a row), Samovar pauses the take-off, sounds a beep and shows the message "Detector: Critical trend! Take-off paused" («Детектор: Критический тренд! Пауза отбора»). The take-off resumes by itself when the sensor delay has passed and the rise has stopped (message "Detector: Resuming take-off after pause" («Детектор: Продолжаем отбор после паузы»)).

- For the first 30 seconds after a line starts, and for a minute after a manual "Continue" («Продолжить»), the detector does not intervene. On the first hearts line after heads it waits for the vapor temperature to stabilize (up to 10 minutes, status "Waiting for vapor to stabilize" («Жду стабилизации пара»)).

On heads the detector only observes; on tails it works with a threshold 1.2 times higher.

 

 

The lines of the hearts take-off program run until the volume specified in the take-off program is collected or the transition temperature (the fifth value of the line) is reached, after which Samovar moves on to the next line.

When the last line of the program finishes, Samovar stops the take-off, moves the sampling unit's rocker arm to position 0 and keeps the column in "self-reflux" («работа на себя») mode for 30 minutes, then switches off the heating and, when the column has cooled down, switches off the water. If the maximum boiler temperature set in the settings is reached earlier, Samovar finishes the program and switches off the heating immediately.