Short path kit reviews (So many to choose from)

Im considering purchasing a china unit from alibaba myself but the kits they sell come with a rotary vane pump and I thought these needed a welch belt driven pump?

Looking at this unit
https://www.alibaba.com/product-det...?spm=a2700.7724838.2017115.214.310833d8D9eTrK

What else would I need to buy to make this work well?

SkyHighLer said:

The high end SPD kits come with temperature controllers that have both power and temperature control. I only know of two plug-n-play controller brands that have both functions, J-KEM's, and Glas-Col's like the 108A L14-1800.

https://www.jkem.com/temperature-controllers/precision-controllers/model-210-controller

https://www.glascol.com/precision-controllers


Or here's a better controller that anyone should be able to wire up themselves for less than a couple of hundred bucks. Controller, solid state relay/heatsink, thermocouple, and an extension cord for wiring, maybe a project box.

Still Heat Controller for Distillation Process Automation
Starting at: $67.95

Model: DSPR220

https://www.auberins.com/index.php?main_page=product_info&cPath=53&products_id=559


"Application Example for Alcohol Distilling

Set the high power accelerated heating limit to 170.0°F (76.7°C) and power output to be at 100% of the element capacity, set distilling power at 30%. Set the foreshots/heads alarm at 172°F. Set the distillation ending criterial to be either when temperature rise to 175.0 °F or when the time is more than 3 hours. When the controller is powered up, it will heat the wash with full power. After the wash temperature reaches 170°F, the power is automatically reduced to 30%. When temperature reaches 172°F, the alarm will beep four times to notify the operator that temperature is close to the alcohol boil temperature so that he can remove the heads. Soon the temperature rise to 173.0°F, the timer is activated. After distilling for a while the content of alcohol is depleted and temperature starts to rise. Once the temperature reaches 200.0°F, the heater is turned off and the controller will send long beeps and flashing "End" on the display. if the temperature does not rise to 200.0°F after 3 hours, the heater will also be turned off. During the distillation, the user can use the rotary knob to fine tune the boil at any time. The figure below shows how the power is correlated to the temperature and time."

https://auberins.com/images/Manual/DSPR220_manual.pdf

https://auberins.com/images/Manual/DSPR400_manual.pdf

Auberins has DIY kits and plug-n-play options, about $300 ready to go.

https://www.auberins.com/index.php?main_page=product_info&cPath=64_65&products_id=533


Or, I devised a setup utilizing a Variac for the power regulation which provides the advantage of being able to overdrive the heater at 130% of it's rating.

https://www.icmag.com/ic/showpost.php?p=8050263&postcount=240

https://www.icmag.com/ic/showpost.php?p=8064606&postcount=241

https://www.icmag.com/ic/showpost.php?p=8067913&postcount=243

https://www.icmag.com/ic/showpost.php?p=8069624&postcount=244

https://www.icmag.com/ic/showpost.php?p=8073018&postcount=246

https://www.icmag.com/ic/showpost.php?p=8074191&postcount=247

https://www.icmag.com/ic/showpost.php?p=8075322&postcount=248

Click to expand...

SkyHighLer said:

Lab Society now has their own temperature controller with power regulation as described in my quote.


Digital Temperature Controller And Monitor
$1,305.00

https://labsociety.com/lab-equipment/digital-temperature-controller/

Click to expand...

There is profuse documentation explaining the J-KEM power regulator control in the manual,

https://www.jkem.com/files/manuals2/210_Manual.pdf


Section 1.2
Set the power level switch to the volume of solution being heated
(not the size of the flask being used). The power level switch can be thought
of as a solid state variac. Volume ranges are printed above this switch as a guide to select the correct power level since it’s easier to guess the volume being heated than the appropriate “percent power” to apply to a heater. ‘Heat Off’ turns off the heater so the controller displays temperature only. All new users should read Section 3.6.


TIP: Because the power switch acts like a variac, if the reaction is heating too slowly or you need more power (e.g., heating to high temperatures), give the heater more power by turning the power level up one setting. If the reaction needs less power than normal (e.g., heating to low temperatures (<60o C) or the temperature overshoots the set point excessively, turn the power down one setting. DO NOT set the power switch on a setting too high initially to heat the reaction quickly and then lower it to the correct setting, this degrades heating performance.


3.6 Power Reduction Circuit. This circuit (12) is the interface to J-KEM’s patented power control computer which limits the maximum output power delivered by the controller. It determines whether the controller heats at a very low (1-10 mL), low (10 - 100 mL),
intermediate (50 - 500 mL), medium (300 mL - 2 L), or high (>2 L) power level.

The power reduction circuit acts as a solid state variac. This circuit has an additional setting: “Heat Off” which, when selected, turns heating off and allows the controller to act as a digital thermometer. The table to the right shows the maximum output power from the controller to the heater depending on the position of the power switch. The correct setting for this switch is the setting that supplies adequate power for the heater to heat to the set point in a reasonable period of time while at the same time not overpowering it. See Section 4.4 for a detailed explanation of how to correctly set up a reaction using your J-KEM controller.

(followed by a few pages of detailed examples ending with,)

The power reduction circuit limits the total amount of power delivered to the heater. In this sense it works like a variac and can be used like one. If the heater isn’t getting enough power, turn the power level up one notch, if it’s getting too much power, turn it down.


Section 4.1
2) Again referring to the range analogy, you'd obtain better control when heating small volumes if the range had more than two power settings; Off and High. J-KEM’s patented power reduction circuit (12) serves just this function. It allows the researcher to reduce the power of the controller depending on the amount of heat needed. This circuit can be thought of as determining whether the heating power is Very low (1-10 mL), Low (10-100 mL), Intermediate (50-500 mL), Medium (300 mL-2 L), or High (> 2 L). The proper power setting becomes instinctive after you've used your controller for awhile. For additional information see Section 3.6.



The Auberins controller does it all, with more precision (smooth 0-100% regulation) for way less moola.

Rather than just conjecture, I put my money where my mouth is and bought one of these advanced controllers with temperature control and power regulation, and posted up here:

https://future4200.com/t/distillation-controllers-with-both-temperature-and-power-control/1560

I hope one or more of the SPD vendors will incorporate the Auberins controller into their packages. If so, thanks in advance!!

(Sorry for not reposting the whole thing at ICMAG Forums, I haven't been feeling well.)

SkyHighLer said:

Rather than just conjecture, I put my money where my mouth is and bought one of these advanced controllers with temperature control and power regulation, and posted up here:

https://future4200.com/t/distillation-controllers-with-both-temperature-and-power-control/1560

I hope one or more of the SPD vendors will incorporate the Auberins controller into their packages. If so, thanks in advance!!

(Sorry for not reposting the whole thing at ICMAG Forums, I haven't been feeling well.)

Click to expand...

Sorry to keep banging the drum, but what I discovered for myself, and what I keep finding reference to, is that for boiling/distilling a PID controller is not the way to go!! (Yes, a PID controller is magic when trying to hold a liquid at a set point beneath the boiling point, your general purpose lab hotplate/stirrer should have a PID controller.)

The thread referenced in the quote, "Distillation controllers with both temperature and power control," now contains everything I know, it's basically a blog, and everyone should read through it.

https://future4200.com/t/distillation-controllers-with-both-temperature-and-power-control/1560

In it you'll find detailed explanations, pictures, and wiring diagrams for the five ways I post about to achieved smooth power regulation.

Five ways to precisely regulate power:

1 Variac alone (a 20 amp unit from eBay for about $75 is recommended)

2 Rotary encoder power regulator with solid state relay (Auber DSPR1)

3 Temperature controller with PID or ON/OFF or Limit function with an external heavy duty mechanical relay to control the temperature when using either a Variac or rotary encoder power regulator (Auber SYL-1512A2 temperature controller)

4 Temperature controller with PID or ON/OFF or Limit function with it’s internal mechanical relay used to interrupt the solid state relay signal from a rotary encoder power regulator (Auber SYL-1512A2 temperature controller and a Auber DSPR1 power regulator and a solid state relay)

5 Rotary encoder power regulator designed for distillation with solid state relay (Auber DSPR220 or DSPR400)


I found this clincher yesterday, it's the controller thread from the mandatory 'read before you can make your first post' sticky threads at Home Distiller Forums.


Why you need a controller and what kind. (Electric heat)
Postby Prairiepiss » Wed Nov 06, 2013 10:00 am

There is always a lot of confusion about the need for a controller when an electric element is used to heat a still boiler and or an electric heat source like a hot plate. So I would like to clear things up a bit with this post. It's not about which controller is best to use. There are plenty of threads about the different types of controllers. This thread is about why you need one. And what that controller needs to do for you.

Since you are reading this I am assuming you have already researched and learned the basic theory of distilling, if you have not, you should do so before getting too deep into this subject, otherwise you won't fully understand what is being said here.

Basic distilling:
You need to boil the liquid in the still boiler to produce alcohol vapors that can be recondensed into a higher ABV distilled spirit. The temperature that that liquid will boil at is dictated by the ABV of that liquid since it is a mixture of alcohol and water. It will be somewhere between 173f/78c (boiling point of 100% alcohol) and 212f/100c (boiling point of water). The higher the ABV the lower or closer to 173f/78c the boil point will be. The lower the ABV the closer to 212f/100c the boiling point will be. There are charts available to figure exactly what that boiling point will be.
Alcohol content of Wash

Just remember. You cannot control the temp of the boil the amount of alcohol does this.

This now leads me to why you need a controller for your electric heated still.

You need to be able to adjust how fast the liquid is boiled off. This controls how much vapor is produced. Less heat makes for a slower boil. And will make lower amounts of vapors produced. More heat will make the liquid boil faster. Producing more vapors. You need to be able to adjust the amount of heat. That you put into the still boiler. So you can adjust the amount of vapors produced and sent into the still head. I will give you a couple of examples.

Pot Still
On a pot still you control the takeoff rate not temps. To do this you need to control the amount of vapors that are sent to the condenser. Again The slower the boil less vapors are made. So you get a slow takeoff speed on a properly configured system. A steady takeoff rate of drips per second should be achievable. In the lower heat settings when you crank the heat up the amount of vapors created by the faster boil increases, thus more vapors are sent to the condenser and the takeoff rate increases. Do not exceed the condenser limitations. Allowing alcohol vapors to be pumped into the air. The top speed you can take product off is limited by the product condenser being used in your still. But a good takeoff speed for a pot still is somewhere between a steady broken stream and a steady twisted stream. You can only achieve that by adjusting the amount of heat put into the boiler to get the liquid to boil off at the correct rate to produce the right amount of vapors. If you don't have control over the heat it will either be to slow of a takeoff speed or to fast of a takeoff speed. Vary seldom can you achieve the correct takeoff speed without a controller. Keep in mind that the ABV of the liquid in the boiler will affect the amount of heat needed. So a 10% wash will take more heat to get the correct takeoff speed than a 40% low wines still charge. So you need to be able to compensate for this by being able to adjust the amount of heat. A setting that works for a 10% wash will be too much for a 40% low wines so the takeoff speed would be too fast. As the run progresses the ABV in the boiler goes down thus the heat needed to maintain the same takeoff speed will increase.

Reflux Stills
There are many different types of reflux stills but the same basic rules apply to all of them.
On a reflux still you want the proper amount of vapor sent to the column to produce the proper amount of reflux for the still to work at an optimum level. Too little heat results in too little vapors and reflux giving you poor results and shows up as higher temps on the columns thermometer. This results in a lower ABV product because not enough reflux is returning to the column for the packing to work properly. Not having the proper amount of reflux returning to the column will not allow the needed column temp gradient to be achieved, more hot vapors than cooler returning reflux showing a higher temp than wanted. Now a too high of a heat input creating to many vapors will more than likely flood the column where there is too much reflux returning to the column and to much vapors coming from the boiler causing the vapors to hold the reflux in the column not allowing it to return to the boiler. This will cause a safety problem and poor performance. You need to be able to adjust the heat input to achieve the correct amount of vapors to achieve the correct amount of returning reflux and rising vapors in the column. This is different for every still. And as above the ABV of the boiler charge will also change this so it needs to be adjusted for your particular still setup. There isn't a one size fits all type heat setting it's all as per still.

Now on to the kind of controller like I said this is not about the best controller. It's about what that controller needs to be able to do for you. The controller needs to be able to adjust the amount of heat being put into the boiler. In a steady variable amount you want the heat to be as steady as possible. You do not want it cycling on and off wildly. If cycle times are more than say one time a second. It's more than likely not a good choice because every time it cycles on more vapors are created. Then when it cycles off no vapors are created and you get surging. It would be like if you were trying to use a hose and your kid was around the corner pinching off the hose and laughing at you because the hose sprays then shuts off, then sprays and shuts off again. This variance in vapor amounts can and will wreak havoc on the still operation causing surging which in turn will cause smearing of the heads hearts and tails and it can give you false readings on a thermometer in a reflux column.

The other thing you do not want is a controller that works off of temps. A thermostat controller or PID controller (without manual mode) are examples. First off we can't control a still by boiler temp. As it will be ever changing and these types of controllers cycle very widely. They reach the set temp while at full power then shut off all power till the temp drops below the lower setting which is usually a long time span. Since it’s trying to control temps and you are trying to control amounts of vapor produced the temp settings usually get set high so you get really long surges of full power heat. All this creates bad surging within the still and the same holds true as stated above about the surging.

There are many types of good controllers out there. And many good threads on all those types of controllers. Please do your own research as to which one of those will be best for your situation. As long as it does what I mentioned above it will serve you well.

https://homedistiller.org/forum/viewtopic.php?f=62&t=43024



The conclusion you should have reached is that you absolutely don't want a PID controller on your heater/mantle, and you can do way better than the analog power controls found on the cheap Chinese mantles as they have limited precision. Either bypass the heater control on your mantle and feed the heater directly with a proper controller, or buy a mantle without a controller like the Glas-Cols, and plug it into a proper controller.