Heat and Controller question

[Autorotate44]

Hi all, I'm new here, haven't even bought anything yet, I'm working my way through the MOUNTAIN of reading and knowledge that HD has... thank you all.

I'm to the point in my learning that I'm considering a band heater around, and a hot plate under my boiler. The band heater, I'm thinking about plugging into a controller, and the hotplate directly into the wall.

I want to make sure I"m understanding the need for a controller correctly. From what I've read, it seems that my hotplate will act like any electric stovetop and be either 'all on' or 'all off' depending on where i set the temp... ie: if it's on low it will be 'off for 9 of 10 seconds and on for 1 of 10, and if i put it on high, it will be always on.... this i believe would be good at the beginning, until the temperature at the top of my still (i don't remember the name of that part right now) reaches a certain point, and then I could unplug the hotplate and use just the band heater that is plugged into a controller... the controller changes the way the band works from the electric stove 'on/off' model to one that is always on.... but with varying amounts of power, and therefore heat.

Right? If I'm wrong, send me back to the reading.... but I think I've finally got it?

[still_stirrin]

Well, you CAN’T run a potstill by “temperature”. If you have to ask.....you haven’t read enough! Go back to reading.

And thermostatically controlled heaters, beit a hotplate, stovetop, or belt heater won’t work for you because they all cycle on and off, but as the temperature approaches the “set temperature”, they cycle on less and less. It is the heat input (not temperature) that generates the vapor production rate. With a thermostatically controlled heater, the vapor production goes to zero at the set temperature.

I doubt your approach to heating a boiler will be effective for you. There are better methods. So, study up!
ss

[NZChris]

Heat rises, so a band heater is probably the worst option for heating a still.

Electric control is best done by controlling the power, not the temperature, to get a nice output stream.

[acfixer69]

If you have been reading here at HD I am sure that no one has suggested that a band heater and a hot plate would be a good choice for a heat source. Controller is required but you need to figure out why it need to be a steady rate of heat input. Need to read some more.

[Autorotate44]

Thanks all... i have seen that the bands are NOT recommended, but I thought through my reading that i might have stumbled upon a combination that would work. Apparently not. Back to the reading. I'm going to have to figure out an electric heat source, and I suppose the band idea is out... back to the reading list.... I'm going to search 'heat source' 'electric heat source' and am open to other suggestions or if you know of a thread I should check out.... I'd like to read it all!

[still_stirrin]

....I'm going to search 'heat source' 'electric heat source' and am open to other suggestions or if you know of a thread I should check out.... I'd like to read it all!

Have a look at my hotplate modification linked in my signature. It works for my 16 quart stock pot potstill. Not enough element contact for a keg boiler, so better options exist. Search them. But, my hotplate build might work for a small still.
ss

[Autorotate44]

Well, you CAN’T run a potstill by “temperature”. If you have to ask.....you haven’t read enough! Go back to reading.

And thermostatically controlled heaters, beit a hotplate, stovetop, or belt heater won’t work for you because they all cycle on and off, but as the temperature approaches the “set temperature”, they cycle on less and less. It is the heat input (not temperature) that generates the vapor production rate. With a thermostatically controlled heater, the vapor production goes to zero at the set temperature.

I doubt your approach to heating a boiler will be effective for you. There are better methods. So, study up!
ss

I'm going to go back to reading, but curious if you read my post, because I think what you're describing here is what I think it means in my OP? (about it cycling?)

Also, by running a potstill by temperature, i think you're meaning that the temp will change as ethanol rises and the amount of alcohol in the boiler is lowered it will change the temperature required... am i on the right track? Either way, I wasn't trying to say that I would run potstill by temperature, but rather that at some temperature I would eventually learn that I'm nearing the point at which I would start to see distillate coming from condenser.... ? Am i way off base here?

I'm reading the hotplate mod in your sig now, and leaning towards an internal hot water heater style element now, because I'm definitely no electrician! haha

[acfixer69]

Give this a good read several times over a few days until you really understand it. With that building or buying a controller is just a choice.
http://www.kelleybarts.com/PhotoXfer/Re ... gMyth.html

[Saltbush Bill]

i think you're meaning that the temp will change as ethanol rises and the amount of alcohol in the boiler is lowered it will change the temperature required... am i on the right track?

Your getting the idea.

[Yummyrum]

Autorotate44
I believe you do have the concepts right in your head , IE you understand that you can heat the boiler up to with full power and then when its close to boil you switch to a lower power . I also think you have understood correctly that the stove top cycling is not a good thing and have realised that the power controller in the heat belt uses a different style of control which is better for distilling .

So you just now need to look at some better designs of the Phase controllers used in that heat belt that can handle a larger element .

There are many builds on here that you can easily DIY . These consist of basically a potentiometer , a special SSRV , a heatsink and a box to put it in .

https://stilldragon.com/diy-controller-kit.html

Then there is another common phase controller option for DIY which is a pre-built module called ( although incorrectly ) an SCR controller .These are a dim a dozen on fleabay

https://www.ebay.com.au/itm/10000W-High ... f58c69a289

BCE1182D-208F-436E-AC74-CE9FF73728C7.jpeg (23.42 KiB) Viewed 1244 times

Then there is an another approach that uses a aligjtly different method to phase control but is equally as good and justifiably better . It uses a burst fire control method and power level can be accurately set in 1% steps from 0-100%

https://www.auberins.com/index.php?main ... cts_id=444

Note that the DSPR1 has to be connected to a SSR40VA SSR to work .

Also note that this type of SSR is a totally different animal to the SSRV that is used with a pot .