The 555 Power Controler

[mrtom]

Jumpin Jesus on a pogo stick! You must have been well stocked?[/quote]


I had two 23 litre carboys of 90% neutral layed away, plus whatever I had previously flavoured and bottled. It has been more than a couple of years to be honest. Its more like 6 years (since i began working at my current job and had a couple of children) time seems to fly by.

[whiskymonster]

i have actually built the 555 timer circuit with the twin diodes, and seeins as i didnt have an ssr knocking about, i used a couple of 16a mechanical relays twin linked together. im waiting on a 4 1/2 gal ss keg to fit an element to, so i havent tested on the still, but it switches a 3kw elctric heater well enough. i have set the time period to about a second, and it ticks away quite happily with a range of about 5% to 100%.

the eventual plan was to fit a thermistor to the boiler, and link it into the 555 to acheive a nice steady temp in the boiler. maybe an override to keep the element on full until i get close to temp.

what do we reckon guys, any mileage in the feedback sensor, or just do it with a twist knob?

j

[rad14701]

whiskymonster, scrap the idea of monitoring the temperature in the boiler... That's not how you run a still... All you are concerned with is vapor temperature at the top of the packed column and being able to knock down 100% of that vapor with the reflux condenser... Monitoring the boiler temperature tells you nothing of value as both the wash and vapor temperatures within the boiler will rise throughout the course of every run and they have zero correlation with the vapor temperature at the top of the column... Make sure you have a full understanding of reflux column theory before investing time into any form of automation... If you can't run manually with proficiency you will never be able to automate the process... Perhaps you do know the theory but from the previous post it doesn't sound that way...

[likkerluvver]

There might be one good use for boiler temperature monitoring:

When using over-sized elements/gas burner for a speedy warm-up, it would enable you to be sure to power down to a more suitable heat input - well before the first fore-shots.

[whiskymonster]

i understand that the way to control the vapour temp at the top is through reflux control, as the richer vapour wil be presenting a lower boiling point. i have read about heating managment stills, and have never heard anything good about them from anyone.

was just thinking that a regulated boiler might even out the lumps a bit, making it easier to control the liquid
if theres no mileage in it, then fair enough.

im running on the electric stove atm, and the larger rings switch on and off too slowly, and the smaller ones run a lot more smoothly, but take an age to heat up. the control would just stop me having to slide from one ring to the other once i warm up.

i have a couple of kettle elements, but they're quite tight wound. this means if i just use one, all the heat will be over one side. not sure if that would be such a problem, but even heat would be preferable.
2 would add up to 4000watts, way too much for my purposes, so i would need to pulse them. i might put a stat on the outside of the boiler, to keep at full until i get close to boiling, and then switch over to the variable supply.

that said, it might be easier to buy a dedicated little hotplate and plug straight into the regulator. that would also save me having to drill the stainless, but we shall see how i feel when i have the cash to upgrade.

j

i fact, now as i say it, the hotplate is sounding like a hell of a lot less trouble.
ebay here i come...

j

[rad14701]

Just tossing this in for shits and giggles... Tossed some figures into my calculator page and here is what I found...

A electric element producing 2000 Watts will heat 5 gallons of wash in roughly 45 - 60 minutes and that same 2000 Watts will maintain a vapor speed within a 2" reflux column of roughly 29 inches per second, which is close to optimal... Real world results may vary slightly but I've found that most of the preliminary calculations I use prove fairly accurate in practical application...

I guess what I'm trying to convey is that the concept of more is better isn't always the case... Sometimes more is, well, just more...

[MuleKicker]

i have actually built the 555 timer circuit with the twin diodes, and seeins as i didnt have an ssr knocking about, i used a couple of 16a mechanical relays twin linked together. j

Mechanical relays aint gonna last long running like that. You need to go solid state.

[whiskymonster]

ill invest in solid state when i gots some upgradin cash.
as for the mechanical ones, i have about a dozen of em i bought as a job lot on ebay a while back, so im not too worried about it until then!

[mrtom]

i understand that the way to control the vapour temp at the top is through reflux control, as the richer vapour wil be presenting a lower boiling point. i have read about heating managment stills, and have never heard anything good about them from anyone.

was just thinking that a regulated boiler might even out the lumps a bit, making it easier to control the liquid
if theres no mileage in it, then fair enough.

j

No matter how much heat you pump into a boiling liquid mixture, it will not exceed the boiling tempurature (tempurature of transformation) for that particular solution - which makes boiler tempurature control a moot point, unless you are only interested in maintaining the boiling point of the liquid with the least amount of heat input, in which case you will only be producing very little vapour to work with in your column. The more heat you put into the wash, the more vapour you will produce in a specified time, but the tempurature of the wash will not change above its boiling point until the composition of the solution changes.
In my opinion you would be wasting your money on automating the boiler. As others have said, what you want to do is maintain a certain vapour speed in your column and be able to reflux all of it and then withdraw it in a controlled manner.

In short, you will be setting your vapour speed (rate of evaporation) with your heat input and fine tuning or balancing it with your reflux and rate of withdrawal, no matter which method of still management you prefer. With duty cycle or phase angle you should be able to control your heat input closely enough that there are no lumps to smooth out. In effect by controlling the BTUs into the boiler, you are directly controlling the rate of vapour produced, without ever changing the tempurature of the wash. I hope that makes sense.
In reading about the phase angle control, the thing that I am liking is that you can measure your heat input with an amp meter, enabling more repeatability than the duty cycle I am using. This might make it worth while for me to experement with.

[HeadCase]

Now I can finally use those old 555s that I have left over from all of my Electronics Classes in High School and College!

[rad14701]

Here's something to ponder for those thinking about using 555 power control instead of phase angle power control...

With a 555 power controller you have no real way of determining the amount of power applied whereas with a phase angle power controller you can measure and multiply voltage and amperage to come up with a realistic measurement... Or, based on the resistance of the element, and some initial calculations, you can determine the power output based solely on voltage...

Also, with a 555 based power controller you need both AC and DC voltage in order for the circuit to work... The power output is also non-linear... The power is 100% for a given amount of time and then reduced to 0%... The only way around this downside is to have the timing at a high enough rate to eliminate the on-off cycling... This can be done by increasing the rate of on-off cycling to a multiplier greater than the frequency of the AC, either 50Hz or 60Hz, switching on and off more than 100/120 times per second... But then you have the issue of the DC switching not being properly timed in phase with the AC causing ripples...

I've experimented with both, at length, and 555 power control will never be as efficient as phase angle control... If you aren't looking at using it in conjunction with other electronic circuitry the additional costs and complexity aren't worth the effort... Oh, and then there is the printed circuit board... You would end up with cleaner power by using the simplest of phase angle circuits consisting of a triac, a diac, a resistor, a capacitor, and a potentiometer...

Just wanted to convey that although 555 power control can be done, there is no real reason or benefit behind doing so...

[HeadCase]

Here's something to ponder for those thinking about using 555 power control instead of phase angle power control...

With a 555 power controller you have no real way of determining the amount of power applied whereas with a phase angle power controller you can measure and multiply voltage and amperage to come up with a realistic measurement... Or, based on the resistance of the element, and some initial calculations, you can determine the power output based solely on voltage...

Also, with a 555 based power controller you need both AC and DC voltage in order for the circuit to work... The power output is also non-linear... The power is 100% for a given amount of time and then reduced to 0%... The only way around this downside is to have the timing at a high enough rate to eliminate the on-off cycling... This can be done by increasing the rate of on-off cycling to a multiplier greater than the frequency of the AC, either 50Hz or 60Hz, switching on and off more than 100/120 times per second... But then you have the issue of the DC switching not being properly timed in phase with the AC causing ripples...

I've experimented with both, at length, and 555 power control will never be as efficient as phase angle control... If you aren't looking at using it in conjunction with other electronic circuitry the additional costs and complexity aren't worth the effort... Oh, and then there is the printed circuit board... You would end up with cleaner power by using the simplest of phase angle circuits consisting of a triac, a diac, a resistor, a capacitor, and a potentiometer...

Just wanted to convey that although 555 power control can be done, there is no real reason or benefit behind doing so...

rad, for our at home tinkerers of electronics, you have any example diagrams of phase angle controllers that you have tried? Are these made or bought off the shelf?

[rad14701]

rad, for our at home tinkerers of electronics, you have any example diagrams of phase angle controllers that you have tried? Are these made or bought off the shelf?

Yes, I have several schematics that I will be posting or have already been posted in other topics... I'll be grouping them together in a new topic, hopefully in the near future... All of the ones I have built and tested are for 120V only... I don't have immediate access to 240V here so I'd have to build one and test it elsewhere...

[Mashy]

Okay, the controller is way beyond me but my builder is going to help me out with running a 50 amp service with 6/3 wire. I will be running a 5500 watt element with a controller. Is 50 amp and that thick ass wire overkill?

Should I just be installing a 30 or 40 amp service with 8 to 10 wire?

All the "professional" help I've received is from Home Depot. I went twice and two different employees recommended the same thing so I thought I was good to go. Now, after reading several posts, I'm thinking a 30 amp service would work fine.

What type of breaker and wire would you all run for a 5500 watt element w/controller?

[Mashy]

I've just found a pretty good idea of what I need on the web. 30 amp with 10/2 (orange) wire I'm thinking. Here's a cheat sheet.

http://waterheatertimer.org/Figure-Volt ... eater.html" onclick="window.open(this.href);return false;" rel="nofollow

[Mashy]

Wired up the 30 amp service today. Not as hard as I thought. Now I just need a controller. Anyone want to build one for me? Rad, I can run your test unit here.

[jake_leg]

Kudos to the OP for this very informative tutorial.

In reply to Rad, I have built a similar controller that used a programmable microcontroller as a timer instead of a 555. I use it to control a 3 kW heating element (13 A, 240 V). The power response is linear. Rippling is negligible. The component parts are cheaper than those for a phase angle controller. It does require an external DC source. You could use a battery. Not a biggie. And I etched no circuit boards. In fact you don't need a soldering iron, you can build the whole thing on a breadboard. No flickering lights, no radio noise. It works fine.

But the easiest solution (in UK at least) is just to buy a Kemo M028N. Available on ebay.de for less than GBP 25 delivered. At that kind of price why build anything.

[rad14701]

jake_leg, I have read that topic on AD and have followed it from the start... I seem to recall there being other associated topics as well...

I honestly have to disagree with your statement that you can build an IC based controller cheaper than a phase angle controller because phase angle can be done without a PCB entirely... Depending on how exacting the controller needs to be, and for powering an element it doesn't need to be overly exact, you can use a minimum of parts if hysterisis isn't a concern, which it isn't, or can get only slightly more complex to attain 5% - 95% duty cycle... Add a bypass switch for 100% and you're good to go...

I have enjoyed tinkering with electronics for over 40 years but most members wanting a controller just want something that works as cheaply and simply as possible... I mean no disrespect to your efforts, I just don't see the 555 or other IC based controllers as being any more useful for the average home distiller... And anyone who ventures into them probably knows enough about electronics to get to where they want to be already anyway...

All that being said, I do like seeing different means to the same end... There's more than one way to skin a cat - not that I've ever skinned a cat...

[jake_leg]

Fair enough Rad.

All that being said, I do like seeing different means to the same end...

+1

[seaguy]

Thanks for your efforts FDM. I too will be using your 555 diagram. I had to pay almost $4.50 (shipped) for a 40A SSR. Already had the rest laying around. Glad I saved some junk circuit boards and who doesn't have excess ac adapters laying around?

[seaguy]

I thought It prudent to ad that those of you considering the NE555 method should know that some experience is a real boon to being successful. It is very easy to make a mistake in the low voltage circuit. If the smoke is allowed to escape from any of the electronic components it will not work again and will possibly harm other components as well.
If you want to see the one I made search my 'Boka Build' post. It is a fun project if you like electronics