High Level Overview of PID like Control

[shadylane]

I'm thinking and might be wrong
Since the boiler temp is gradually rising as the alcohol boils off
The boiler temp will never overshoot for the controller to learn from.

Thank you charcoal for your graph I'm using

A PID will try to learn and copy the above operator and will show results like

pid.png (5.5 KiB) Viewed 4477 times

[jonnys_spirit]

[StillerBoy]

So to continue with how I use temp probes, here are the temp probes numbers, as taken during a run done today..

The run consisted of a grain base spirit of 95% - diluted to 43% of 6 gal boiler load, for a re-run.. re-run for the reason of reducing the acidity of the spirit, reducing the Ph level, from a Ph of 5.5 to a Ph of 6.8, once it was diluted to 50%.. reason for the re-run of once at 95%, was for in the making of herbal tincture..

So here goes.. the unit used is a concentric design, 2" x 36" packed with 1/4" lava rocks, 7 gal boiler keg, with 5500 watt element.. note that the steady reading of the top meter, reading 170.3*F is giving an 95% abv at the rate of 2.25 litres per hour in the body..

In first picture (Start of run) the top meter is indicating a temp of 170.3*F from the temp probe located at the top column, just about the packing and just below the vapor throat body.. the meter just below the top one, indicates the temp of 179.7*F from the temp probe located just off the base of column, in the vapor pooled just below the column base.. and the other smaller meter indicating the water temp at the outlet of the reflux condenser..

Note: the temp of the vapors near the base of the column indicate the level of the alcohol abv at the start of the run.. also note that the run has been in reflux mode for about 20 minutes at the time of the picture, and was just at the start removing a small amount of fores and heads (100ml all together)..

The second picture down, the middle meter indicating a reading of 183.2*F from the temp probe, indicates that by the temperature reading that the end of the body section is nearing.. around the 184 - 184.5*F is the transition of the body and the tails.. note that the top reading is steady at 170.3*F and that has be producing an abv of 95% abv.. and the water temp is stable at 81 - 82*F range..

The third picture down, the middle meter indicating a reading of 190.8*F from the temp probe, indicates that by the temperature reading that the run is well into the tails section (early late tails).. from 189 - 194*F.. just that period, in a normal run, I would be collecting compressed tails in small 200 ml amount, and may or may not add them to the body once they've been air and sampled..

The fourth picture down, the meter indicating a reading of 200.6*F from the temp probe, indicates how deep into the run I went.. remembering that this run was about a re-run run, and want to exact as much of the alcohol as possible.. remembering also that this run start off have the cuts done in the previous run, so there were basically no heads or tails to talk of..

Note that the top meter indicates a 170.3*F reading, indicating a 95% abv take off.. also note that to maintain that level of abv, one has to manage it by reducing the take off rate.. also note the the power usage (amps) was slowly increase during the run.. this was done to maintain a level of refluxing to take place..

Mars

Start of run

Just about near the end of body section

Into late tail section

End of run

[StillerBoy]

Below are pictures of the unit used in the above post recording the activity, plus the location of the temp probes..

The first picture down show the concentric unit used in the production of the spirit run..

The second picture down show the location of the temp probe in the vapor path near the base of the column..

The third picture down show the location of the temp probe at the top of the column, located about 1.5" above the packing and just below the vapor throat, and is protected by shield so to not have any reflux dropping on it..
It also the the location of the temp probe monitoring the temperature of the water flow at the outlet end of the condenser..

Mars

2" x 36" concentric unit

Location of vapor temp near base of column

Location of top column probe and water outlet

[shadylane]

Note that the top meter indicates a 170.3*F reading, indicating a 95% abv take off..

Sounds like the temp probes are as inaccurate as mine
Or your locate farther above sea level

[StillerBoy]

Sounds like the temp probes are as inaccurate as mine

It would seem like you are just reading bits and pieces, here and there.. lol

Each temp probe meter is within a tenth of each other, and all reflect the exact temperature in their reading.. took a few extra probes to get it there, and it doesn't matter which probe I plug into a meter, they all give the same reading.. so the meters are good, it just the probes that can be off some..

Mars

[zed255]

Seems some get hung up on the numbers rather than the changes or differences in the numbers. The actual reading is far less important than knowing what you are being told about what is going on.

I fall into the camp of thermometer users for the right reasons, understanding what is going on in the still. I like Mars' approach and agree that we can get good information when we look in the right places and interpret correctly.

[shadylane]

If You want a humbling experience
Do a boiling water run with your rig
And see how inaccurate the temp measurements can be from 212ish

[StillerBoy]

I fall into the camp of thermometer users for the right reasons, understanding what is going on in the still. I like Mars' approach and agree that we can get good information when we look in the right places and interpret correctly.

It does matter if one sets himself up using meters like I've done, or use PID's, one still has learn what going on in distillation, otherwise they are useless tools..

It's one thing to look at numbers.. it's a totally different required to develop an understanding and comprehend of them.. and they teach a lot about the vapor behavior.. half degree here and there make all the different many times.. an area where that is so visible is in the temperature of the water flow at the outlet of the condenser.. a degree one way will show up all the way down the column and right into the vapor temp in the boiler.. at least on the concentric and VL units I have..

Once a person get a good handle on vapor behavior, then the numbers start to make sense.. until that happen, they are just numbers..

Is it important to run a still using number.. No.. But.. it doesn't matter if a still is run by numbers or not, but understanding of vapor behavior is very important.. until that happen, one is just going through the motion, following what other say to do..

I've been running my units with the controller pictured for over 7 yrs now.. always learning the fine tuning required.. i do reconize that one has to start somewhere.. but in the end be a pot, a reflux unit, a flute, the principal of distillation is all the same.. just a slightly different behavior of vapors.. that what I teach a new comer first of all, then how to make a wash that's done in 3 days, then he can decide what unit he wants and what product he want to make..

The problem, as seen here all the time, new comer start ass backward.. and that takes them forever to learn the skill of distillation..

Mars

[StillerBoy]

If You want a humbling experience
Do a boiling water run with your rig
And see how inaccurate the temp measurements can be from 212ish

So what's your point Shady.. you have a problem with what the meter are saying..

Just for your un-trusted self, the probes were check in a few different ways.. and one of those ways was using boiling water.. they read right on..

Mars

[shadylane]

Don't put too much faith in the stills instrumentation
Even in the same vapor path
The location and installation of the TC can effect the readings significantly.
That's why there's often a correction factor included in the calibration

[NZChris]

The location and installation of the TC can effect the readings significantly.

As can a lot of variables. Placement, vapor speed, ambient temperature and air speed, Watts, etc.. Opening a door on a windy day causes increased reflux and changes in the abv and take off rates for all of my pot stills.

[Corsaire]

I think that even if the numbers are not dead on on what science dictates they should be at, if they are consistent the info is still valuable, correct? It's the logging that matters I think?

Also, do your potentiometers control power input or do you use a pid? I'm still electronically challenged...

[NZChris]

Don't let yourself be confused into thinking that certain numbers are important by a Newbie stiller, who can't even make himself a nice sugar wash yet, but theorizes they are in a public forum.

There is plenty of great advice available on this forum from past and present experienced distillers who know/knew how to make nice product with various stills. Plus, don't shortchange yourself by limiting your reading to certain posters, forums, websites, or literature.

[shadylane]

I think that even if the numbers are not dead on on what science dictates they should be at, if they are consistent the info is still valuable, correct? It's the logging that matters I think?

Also, do your potentiometers control power input or do you use a pid? I'm still electronically challenged...

Your correct, there's valuable info even if the measured numbers are off by a few degrees.

I use a phase angle controller, what your calling a "potentiometer"
A PID controller can do the same job but must be used in manual mode.

[Corsaire]

Chris, I've already stated this method isn't for me. Just trying to get my head around it.
I'm trying to stress that there's no magic numbers for a newbie to follow. I've never run my pot by temps.

Shady, I was asking about StillerBoy's setup. Should have been clearer in my question. Those two potentiometers in series for fine control, those control a power controller right?
So Stillerboy, do you drive your rig with a pid? Or do you use a power controller and log various temperatures to see how your run progresses?

Here's my understanding so far. A pid is a closed loop system. Thermometer tells the brainbox how hot say the boiler content is, brainbox tells the heating element to heat up a lot or gently depending on how near the current temp is in regards to the set temp. Correct?

So Cayars, you heat your low wines, not vapour temp, to specific temps that you have found using trial and error. By using the same ferments you claim to make better cuts, correct?
You use this procedure in pot stills.
By boiling off lower volatile components, once your boiler is at a specific temp vapor production stops. That's when you make your cuts.

I'm still (really slowly) putting together my first ccvm. First time electric as well, I have a pot still that sits on a gas burner.
So my idea of how reflux works is that you push the power as high as your column and reflux condenser can handle, and then control reflux (and thus take-off) rate by whatever reflux mechanism your still operates at, lm, cm, vm or any combination.

Doesn't PID interfere with this? As I understand it, you want to have as much redestillations as possible, so the most amount of power to the boiler possible to produce the maximum amount of vapor that your column can handle. If the boiler charge gets at the specified temperature the pid would cut power so no more vapour production. So no more refluxing.

Charcoal, how did you wire your pid? Temp pickup above the packing instead of the boiler?

I might grasp the big picture someday.

[Yummyrum]

Cayers , how are you going with getting a picture or two of your setup for us .... a pic saves a thousand words ... they say .

What PID are you using ?

Is it a PID like charcoal is using driving a SSR__DA type of SSR or is it an Auduino or pi driving an SSR__DA or even a PC or Lappy running some PID program again driving an SSR__DA ..... or are you just using a power controller and doing the PID thing in your head .

How are you doing it ?

[cayars]

@ cayers
Sugar washes have been done successfully by literally tens of thousands of folks. If yours are lousy and no amount of cutting improves them then it is something about your method that is at fault, assuming you are using a well reviewed recipe then the problem can really only be your still or method of running it and it may well be the type of controller you are using causing fractional smearing.

And I too can run sugar washes and cut them correctly. I just don't like the spirit being made. I think it's bland, thin without complexity and lousy tasting. Some people don't like whiskey, tequila, mezcal, gin, rum, beer, wine, brandy or vodka tastes. I don't like sugar wash tastes (or lack of). It doesn't mean there is a flaw in the process, just that I don't care for that product. I also don't like certain styles of beer but that doesn't mean I can't make them correctly.

I think that even if the numbers are not dead on on what science dictates they should be at, if they are consistent the info is still valuable, correct? It's the logging that matters I think?

Also, do your potentiometers control power input or do you use a pid? I'm still electronically challenged...

Yes, you got it. Where you place your probes of course will dictate what they register as well. But as long as you do your logging and base decisions on the same setup that is used every time you're good.

A PID isn't actually needed as has been stated. As long as you can hit temps via any means, you can use the temp readings to your advantage.

The location and installation of the TC can effect the readings significantly.

As can a lot of variables. Placement, vapor speed, ambient temperature and air speed, Watts, etc.. Opening a door on a windy day causes increased reflux and changes in the abv and take off rates for all of my pot stills.

True, but the probes still tells you what is happening INSIDE the still. If someone has an environment that's not conductive to distilling, maybe they should take measures to correct that. Regardless of how you run your still, changing environment variables can cause you grief.

Don't let yourself be confused into thinking that certain numbers are important by a Newbie stiller, who can't even make himself a nice sugar wash yet, but theorizes they are in a public forum.

There is plenty of great advice available on this forum from past and present experienced distillers who know/knew how to make nice product with various stills. Plus, don't shortchange yourself by limiting your reading to certain posters, forums, websites, or literature.

Quit being an ass Chris. If you don't understand the process or don't think it has value, then feel free to dispute the process with valid reasons why the temperature inside the still has no meaning, but quit trying to attack people you don't agree with. I asked in post one to be civil.

No one here is trying to tell anyone how they should run their stills. We are simply sharing knowledge we have and how we do it. There are multiple people in this thread who do use temperature readings to their advantage. Genio & iStill as well as many commercial distillers run by temperature as well as other sensors.


Jump to 6:00 to see temperature being used to drive the batch

So Cayars, you heat your low wines, not vapour temp, to specific temps that you have found using trial and error. By using the same ferments you claim to make better cuts, correct?
You use this procedure in pot stills.
By boiling off lower volatile components, once your boiler is at a specific temp vapor production stops. That's when you make your cuts.

Not sure what you mean by low wines vs vapor temps. I happen to use a temp probe at the top of the boiler in the vapor path (not in the liquid). This really isn't ferment specific or ABV specific as you can adjust target temps based on the ABV you start with. That is more complex and to be honest, I'm not there yet making this type of adjustment on the fly. But for now if I strip to the same ABV I remove this issue. Thus for now I'll always start with say 30% in the boiler to simplify the process.

On a pot yes

I'm still (really slowly) putting together my first ccvm. First time electric as well, I have a pot still that sits on a gas burner.
So my idea of how reflux works is that you push the power as high as your column and reflux condenser can handle, and then control reflux (and thus take-off) rate by whatever reflux mechanism your still operates at, lm, cm, vm or any combination.

Doesn't PID interfere with this? As I understand it, you want to have as much redestillations as possible, so the most amount of power to the boiler possible to produce the maximum amount of vapor that your column can handle. If the boiler charge gets at the specified temperature the pid would cut power so no more vapour production. So no more refluxing.

I might grasp the big picture someday.

Not really. Think about it this way. If you only allow heads or hearts to travel up the column then refluxing is simpler when compacting them. The less smearing the better. So with refluxing you manage both the vapor temps by both the boiler and cooling. But of course the reflux itself makes this far easier and you can drive the boiler more.

Think about what happens on a reflux still when you increase the cooling and start knocking things down. What did you do to the temp in the column at the top? What will happen as you continue to reflux if you measure both the top and bottom of the column? Hint, Stillerboy's described this.

Think about that for a bit and you'll realize you are controlling the temperature in the column and in fact are taking things off at temperature.

Yummyrum, nope, I don't post or send personal pics of things used for illegal purposes on the net. Not a smart thing to do in my book.
If you're looking for a device that can be used easily to control heat, this is pretty ideal. It's PID like but more conventional as well (hybrid if you will). https://www.auberins.com/index.php?main ... cts_id=559 DSPR400 for $12 is the one to get.

It doesn't really matter how you control temp, only that you do (per op post). Same thing being talked about here can be done using propane for example and a very gentle touch on the knob while watching your probe temps. Anyone with an accurate probe and logging can follow along and try this regardless of how they do it.

This spring I'm going to do an auduino or pi (leaning toward auduino) based project that will take this process a step further. When I do this I'll be sharing setup, tool selection and code so anyone can follow and join in. It will start out with controlling both heat and cooling (reflux) which is impossible/hard to do right now with different devices working independently and not working with the same data.

[HDNB]

Chris, I've already stated this method isn't for me. Just trying to get my head around it.
I'm trying to stress that there's no magic numbers for a newbie to follow. I've never run my pot by temps.

Shady, I was asking about StillerBoy's setup. Should have been clearer in my question. Those two potentiometers in series for fine control, those control a power controller right?
So Stillerboy, do you drive your rig with a pid? Or do you use a power controller and log various temperatures to see how your run progresses?

Here's my understanding so far. A pid is a closed loop system. Thermometer tells the brainbox how hot say the boiler content is, brainbox tells the heating element to heat up a lot or gently depending on how near the current temp is in regards to the set temp. Correct?

So Cayars, you heat your low wines, not vapour temp, to specific temps that you have found using trial and error. By using the same ferments you claim to make better cuts, correct?
You use this procedure in pot stills.
By boiling off lower volatile components, once your boiler is at a specific temp vapor production stops. That's when you make your cuts.

I'm still (really slowly) putting together my first ccvm. First time electric as well, I have a pot still that sits on a gas burner.
So my idea of how reflux works is that you push the power as high as your column and reflux condenser can handle, and then control reflux (and thus take-off) rate by whatever reflux mechanism your still operates at, lm, cm, vm or any combination.

Doesn't PID interfere with this? As I understand it, you want to have as much redestillations as possible, so the most amount of power to the boiler possible to produce the maximum amount of vapor that your column can handle. If the boiler charge gets at the specified temperature the pid would cut power so no more vapour production. So no more refluxing.

Charcoal, how did you wire your pid? Temp pickup above the packing instead of the boiler?

I might grasp the big picture someday.

i think you already have the big picture. this is really just a few pages of the musing of bored minds....i.e. how can i twist verbiage and lexicon to make it sound like temperature is somehow more valuable to distilling successfully than energy input.

stick to what works, you'll be happier. when you've made a lifetime supply of booze....add some complications to amuse yourself if you must...i mean i use a thermo to confirm what i know, or maybe make some estimates if i'm bored. peek in the sight glass to watch the pretty bubbles.

it's a long day in the still shack and guy can only read so many novels.

[Slow42]

Stillerboy that is an excellent write up on probe placement and extremely informative. Very nice SSVR controller setup also. This information would be great in a post by its self along with the comments from other members. However I haven’t figured out what it has to do with this post. If you were using a PID that would have been great information? Could you do the same if so inclined with a PID. I think this post as gone off on a tangent which isn’t unusual but so much great information is being hidden within the post for future reference. Search for this great information would be almost impossible.

Cayars I wish you would stop trying to defend yourself to everyone in your responses and get back to the post at hand. Start over if necessary. Basics, show us you know how to operate a still using a PID. As Yummyrum suggested show us the money.
Where’s the beef Your the expert on PID’S here so show us. Stop with the tangents.

[StillerBoy]

If you were using a PID that would have been great information? Could you do the same if so inclined with a PID.

Possibly.. I have understanding of how a PID works, but have never work with one..

But.. to a large extent, the point is being missed by most.. and it is that a still is govern by the amount of power it is provided with.. how one manages this input of power to the still, does not matter if it is done using a potentiometer or a PID..

What matters it the management of the power in relation to the amount of vapor produced.. and in turn how one manages the vapors from there.. and that where the temp probes are of assistance..

Running a still is nothing more than learning the art of managing power in the production for the product wanted and getting maximum efficient from the unit one is using..

Mars

[Corsaire]

But that's where the problem lies, I think.
With a pid you have no control over power, once you approach it's set temperature it throttles power to the element.

What I understand from cayars is that he can control this. I've no clue how. And he isn't willing to share what he does exactly.

[StillerBoy]

But that's where the problem lies, I think.
With a pid you have no control over power, once you approach it's set temperature it throttles power to the element.

There are difference in PID, the same as with potentiometer..

It has already been stated somewhere in this thread which one should be used.. a little reading and research on PID would fill in the lack of understanding.. as I did many yrs back on potentiometers..

Mars

[shadylane]

I think that even if the numbers are not dead on on what science dictates they should be at, if they are consistent the info is still valuable, correct? It's the logging that matters I think?
o your advantage.

The location and installation of the TC can effect the readings significantly.

As can a lot of variables. Placement, vapor speed, ambient temperature and air speed, Watts, etc.. Opening a door on a windy day causes increased reflux and changes in the abv and take off rates for all of my pot stills.

True, but the probes still tells you what is happening INSIDE the still. If someone has an environment that's not conductive to distilling, maybe they should take measures to correct that. Regardless of how you run your still, changing environment variables can cause you grief.

Take a longer look at your probe installation
It doesn't look like it's very insulated from the outside world
So It's not just measuring what is happening INSIDE the still

[6 Row Joe]

Late to the party but I'll throw in my .02. I haven't used my PID for quite a while now. I built a pulse width modulator and have been using that and I like it real well. The PID's have to be adjusted up in temp throughout the run. Basically they have to be re-programmed. With my PWM I just turn the dial to increase the power as needed. My Mighty Mini and the 1400 watt element works well with 7 amps output to the element. As the alcohol boils off, the column temp slowly rises throughout the run. It has been running 3 hours and is just barely over 200° with the same power to the element. If I reduce the power to 6.75 watts the column temp goes down so I know that the 7 a. is just right. Really no different than the guys using gas and adjusting the flame.

[LWTCS]

"Really no different than the guys using gas and adjusting the flame."

That's really it in a nut shell.

Heat input should remain un-interrupted. Either a big flame or a small flame, but always a flame.

Flame = Heat Input = vapor (and pressure)

No Heat Input = No Vapor (also no pressure to drive vapor)

No Vapor = No Reflux
No Vapor = No Product

Can you make the thermostatically controlled devise work? Sure. They're just not optimal for distilling.
Cooking grains? Perfect because we wouldn't be constantly changing the boiling point by drawing one (or more) of the lower boiling point constituents out of the mixture as with distillation.

Better place for distilling is on a proportional valve controlling dephlegmator cooling medium flow rates as long as you can get the resolution dialed in without over driving the poor ole valve.

[Slow42]

Everyone seems to hung up about a PID turning on and off and not keeping the vapor at the temperature you want. When they talk about it turning on and off, probable not a good way to explain it but it’s in milliseconds. Here is a description of how one works.
PID stands for Proportional, Integral and Derivative. These are the elements that work to maintain the correct temperatures in a process. Proportional is the actual variance in temperatures. Integral is the previous variance from the set temperature. Derivative is the predicted future variance. Basically, it all means that it takes a formula to keep the temperature of the boiling water at 212 degrees. That's what a PID Controls.
Example:
PID Control panels are used with medical equipment that needs to be sterilized. The tools need to reach a certain temperature and stay at that temperature for a specific amount of time. That's what's called a single loop setup. A multi-loop setup allows the controller to manage several processes at a time. For example, if you had to operate several ovens at the same time with different temperatures. There are even multi-zone controllers available that have to keep a larger heating element that might have variances in temperature across the entire process.
Maybe this will help in understanding how one operates. From person experience I can set my PID to control temperature to within several degree points. Vapor, water, meat pretty much anything. And yes you must adjust it as the alcohol is removed and more temperature is required. It’s a learning process no different from any type controller. On my PID as with all it can tell you the exactly when power is sent to the element, milliseconds. Which is practical on all the time. My SSVR controller never had a meter so I never knew what was going on power wise but from experience I knew where it had to be. Now it just makes it easier as I can see numbers, necessary no but nice. Nothing can bet a PID for perfect accuracy. Is that necessary no. At least no here.
I plan on using the SSVR as now I can tell exactly what’s going on and yes take notes. Could do the same with the PID but not as convenient. It does take a big of learning vs turning a knob. So is a PID good for a beginner probably not the best choice as Cayars stated. Hope this helps a bit.

[Corsaire]

Mars, I'm reading up on them now. I still don't fully grasp what the I and D do. But it will come together in my mind in due time. I'm not a smart man, but not that stupid either.

It would help if someone using a pid would lay out in detail how he or she runs their setup. Where the temp probes are, what pid, what fiddling is required during the run. Preferably with notes from a real run.

I'm kinda dissapointed cayars isn't willing to do this, it'd help me out tremendously to learn how they work.

[StillerBoy]

Good write up Slow.. expect for one thing..

The management of power usage it to maintain a constant flow of the vapors up the column, not about the temperature.. temperature is only relevant to the production of the vapors..

A constant flow of vapors in a pot mode run, is not all critical, as it is visible by at the take off end, but.. in a column setup in a refluxing mode, constant vapor movement is alot more critical..

So whatever method one uses to achieve that, it's a personal choice only, provided it does the task required..

I have chosen the SSR route for it's simplicity and easy to learn how to use it, and to teach others to see what is happen inside the boiler and column.. working off a stove top works, just not as efficiently, but it still produces vapors..

Temp probe only provide information on what is happening in the invisible world of the column confined..

Mars

[charcoal]

Chris, I've already stated this method isn't for me. Just trying to get my head around it.
I'm trying to stress that there's no magic numbers for a newbie to follow. I've never run my pot by temps.

Shady, I was asking about StillerBoy's setup. Should have been clearer in my question. Those two potentiometers in series for fine control, those control a power controller right?
So Stillerboy, do you drive your rig with a pid? Or do you use a power controller and log various temperatures to see how your run progresses?

Here's my understanding so far. A pid is a closed loop system. Thermometer tells the brainbox how hot say the boiler content is, brainbox tells the heating element to heat up a lot or gently depending on how near the current temp is in regards to the set temp. Correct?

So Cayars, you heat your low wines, not vapour temp, to specific temps that you have found using trial and error. By using the same ferments you claim to make better cuts, correct?
You use this procedure in pot stills.
By boiling off lower volatile components, once your boiler is at a specific temp vapor production stops. That's when you make your cuts.

I'm still (really slowly) putting together my first ccvm. First time electric as well, I have a pot still that sits on a gas burner.
So my idea of how reflux works is that you push the power as high as your column and reflux condenser can handle, and then control reflux (and thus take-off) rate by whatever reflux mechanism your still operates at, lm, cm, vm or any combination.

Doesn't PID interfere with this? As I understand it, you want to have as much redestillations as possible, so the most amount of power to the boiler possible to produce the maximum amount of vapor that your column can handle. If the boiler charge gets at the specified temperature the pid would cut power so no more vapour production. So no more refluxing.

Charcoal, how did you wire your pid? Temp pickup above the packing instead of the boiler?

I might grasp the big picture someday.

My idea of running a reflux is run that much amount of reflux/vapour production that only the lighter portions are passed over to condenser.

There is no need to do as many distillations. And with any A/C heat source, power is cut 100 to 120 times a second. There is no real need to keep the power on non stop. In fact, I used to run a hot plate (Click on/Off type) for weeks and it still let me produce high ABV alcohol.

The probe/Thermowell is in the part after the dephlagmator. I am trying to upload a video today.