Do you really need a pid

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Bobby_M said:
Solid State Variable Relay is basically an adjustable SCR that limits the AC waveform to deliver less than peak power. It's the functional modern solution to that VARIAC (speaking of fancy acronyms).

A lot of the discussion about need vs want vs overkill comes down to perceived effort and cost matched up against utility. I doubt anyone would brew on an EZboil based controller and later determine that it's a waste of technology and makes brewing harder or less enjoyable. It's like a manual power knob with the added (and optional mind you) temp control and digital temperature readout. It's been mentioned before, but it's a minimal increment cost over the most rudimentary power control devices.

If it matter at all, I don't sell controllers yet so I have no financial gain in promoting any of this stuff.
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I am sure that an EZBoil setup would cost a small fraction of the cost of a 240VAC 50A Variac (and weigh only a tiny fraction as much). I use Variacs all the time when servicing and restoring vintage radio gear - but only because PWM isn't compatible with power transformers. I wouldn't use them if there were an economical modern equivalent that would work.
 
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I recently ran across these on eBay:

http://www.ebay.com/itm/131408591986
http://www.ebay.com/itm/140553985193
http://www.ebay.com/itm/140553987088

They include a special type of Solid State Relay (SSR) that takes a potentiometer as an input and outputs a proportional amount of power.

If I were going to build the type of setup you're talking about, this is what I'd use. (40+ years experience in electronics, here!)

I was considering adding one of these in the same box as a PID controller, so I could use either PID or manual power control. (Most PIDs have a manual control option, however.)

(Edit: Oops... I replied before reading the whole thread. I see something like this has already been mentioned!)
 
jimdkc said:
On Variacs... Yes that would work, too. However a 2000 Watt Variac is going to be very large, very heavy, and very expensive!
Click to expand...

A 2KW isn't too bad; maybe 40 pounds and $100 (I bought a new one recently). VERY inefficient, though. I doubt that it would really deliver 2KW for very long without the paint melting. Most electric brewing solutions use much more than 2KW, of course.
 
applescrap said:
Am I calling the potentiometer wrong? Basically just a power dial. Drew a picture, sorry its not very good. My hopes are that I can save someone a lot of money and time if they brew like me.
Click to expand...

you have it right... with this setup you would basically brew exactly the same as you would with a banjo /propane burner.... best guess and adjusting everything manually.

This was the best way to get that done on a controller I built a while back... I had a pid for one element and this for the boil kettle.

http://www.ebay.com/itm/140553987088?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT
 
jimdkc said:
I recently ran across these on eBay:

http://www.ebay.com/itm/131408591986
http://www.ebay.com/itm/140553985193
http://www.ebay.com/itm/140553987088

They include a special type of Solid State Relay (SSR) that takes a potentiometer as an input and outputs a proportional amount of power.

If I were going to build the type of setup you're talking about, this is what I'd use. (40+ years experience in electronics, here!)

I was considering adding one of these in the same box as a PID controller, so I could use either PID or manual power control. (Most PIDs have a manual control option, however.)

(Edit: Oops... I replied before reading the whole thread. I see something like this has already been mentioned!)
Click to expand...

this is what I used for a second controller I built to sell but never did anything with.. seemed like a quality setup.
 
wilserbrewer said:
While most will disagree with me, it is entirely possible to brew electric with nothing more than a gfi power source, a properly rated switch and en element sized for a nice boil at 100% power.

I've done it for years, long before there was any info on the web w/ people using pids, pumps etc etc, back in the early days of e brewing 8-10 years ago can't really remember.

7.75 gallon batch in a 15 gallon kettle with two 2000w 120v elements provides a nice boil at full power.
.
Click to expand...

Yeah. My panel build was delayed when I realized that I had a high, but within reason, boil off rate using one 2000w element for 5 gallon batches and two elements for 10 gallon batches. I prefer having better control with the completed panel, but I was able to keep the pipeline full during the process.
 
Jwin said:
What would be the downside in using something like this?

10000W SCR Voltage Regulator Speed Controller Dimmer Thermostat AC 110V 220V
http://s.aliexpress.com/eiqaY3yi
Click to expand...

I'm guessing that if you take that apart, you'll find this inside:

http://www.ebay.com/itm/140553987088

(Or something functionally equivalent!)

Controller1.png


Controller2.png
 
If that will work I would be willing to sell my contoller and save the money back. What else would I need?
 
Lots of great perspectives and dialogue. Thanks to the OP for bringing it up. I recently just finished a 3 tier gravity fed brewing stand with mounted propane burners. However, I still have all the parts for an electric setup that got put on hold because of not being able to add any new circuit breakers on our new (to us, built in 1960s) house.

All that to say, with the discussion here, I'm considering revisiting finishing an electric setup off existing 120V circuits. Thanks
 
I use the controller kit from StillDragon.com Works like a charm...simple as can be. After the wort comes to a boil, I dial it back to 65%.....off to the races.
 
I recently built out an electric system to what I believe you're trying to do. I too was unable to put in any more breakers (which sucks) so I had to use my dryer outlet.

I can dial down for 5 gallons when needed and boil up to 12 with no problem.

I'd love to (and been meaning to) share some pics but I'm at work right now. Will update soon.
 
jimdkc said:
I'm guessing that if you take that apart, you'll find this inside:

http://www.ebay.com/itm/140553987088

(Or something functionally equivalent!)
Click to expand...
I believe an SCR setup is different than an ssvr setup... I may be wrong here but from memory I believe the ssvr still works like a pwm by adjusting the time length of the full power pulses and the SCR actually adjusts the voltage output to a lower voltage....
There are a number of folks here that use those SCR units also found on ebay and more than one have found they are designed for 50hz power and they dont have as linear of control with 60hz power from what Ive read. Also the internal fuse trace and holder has a tendency to burn up on the board over time.
 
augiedoggy said:
I believe an SCR setup is different than an ssvr setup... I may be wrong here but from memory I believe the ssvr still works like a pwm by adjusting the time length of the full power pulses and the SCR actually adjusts the voltage output to a lower voltage....
There are a number of folks here that use those SCR units also found on ebay and more than one have found they are designed for 50hz power and they dont have as linear of control with 60hz power from what Ive read. Also the internal fuse trace and holder has a tendency to burn up on the board over time.
Click to expand...

Whether an SCR circuit works with 50hz or 60hz or whether it offers linear control is a function of the design of the control circuit. Personally, I'd buy the SSVR/Pot/Heatsink and package it myself rather than trust the Chinese SCR controller.

SSRs and SSVRs usually have SCRs or TRIACs (essentially a bi-directional SCR) inside.
 
jimdkc said:
Whether an SCR circuit works with 50hz or 60hz or whether it offers linear control is a function of the design of the control circuit. Personally, I'd buy the SSVR/Pot/Heatsink and package it myself rather than trust the Chinese SCR controller.

SSRs and SSVRs usually have SCRs or TRIACs (essentially a bi-directional SCR) inside.
Click to expand...

hmm well all the ones on ebay and amazon like the one linked were built for the 50hz market... Im just repeating what I read in another thread where someone was asking why they were having those issues with them and the guy from brumatic explained it was because of the 50-60hz difference.. apparently he looked into using them on his panels.

and as far as the SSR using triacs... I am not so sure they all do, especially the ones most home brewers buy.. some use use an optical switch with a Thyristor gate although I admit I dont know much about them but I did a little reading on the differences when there was a lot of discussion on the fake fotek clones a while back.

I made the same choice and went with the ssvr and pot from ebay myself... for my main system I will be replacing my mypin pid with manual mode with an auber ezboil unit for its other features like timed boil and internal alrms and such ..besically more toys for my brewing enjoyment and to make the process as consistent as possible between brews. I totally understand wanting to keep it simple though.
 
DavidD said:
All that to say, with the discussion here, I'm considering revisiting finishing an electric setup off existing 120V circuits. Thanks
Click to expand...

Do it! I have a 2x1500 watt set up. Been using that wattage for about 1.5 years now and I love it. I can brew anywhere I can get to two separate 15 amp circuits, which is never a problem.

And I can make batches as small as 3 gallons and up 10 gallons at 1.050, no sparge. Two weekends ago I did a 9 gallon no sparge Helles Bock with OG of 1.067.

Boiling that much water is no problem with two 120v elements. When I hit boiling I leave one element full blast and turn the other element down to 30% for 6 gallon batches. I use 50% for 10 gallon batches.

I'll say it again. Do it! :)
 
augiedoggy said:
hmm well all the ones on ebay and amazon like the one linked were built for the 50hz market... Im just repeating what I read in another thread where someone was asking why they were having those issues with them and the guy from brumatic explained it was because of the 50-60hz difference.. apparently he looked into using them on his panels.
Click to expand...

That's possible... however, if the triggering circuit is well designed, 50 or 60 Hz won't matter. (The cheap ones may not be well designed!)

and as far as the SSR using triacs... I am not so sure they all do, especially the ones most home brewers buy.. some use use an optical switch with a Thyristor gate although I admit I dont know much about them but I did a little reading on the differences when there was a lot of discussion on the fake fotek clones a while back.
Click to expand...

An SCR and a TRIAC are both types of thyristors... Most have some kind of optical isolation internally.

I made the same choice and went with the ssvr and pot from ebay myself...
Click to expand...

I think this is the easiest, most cost-effective solution.
 
No. I'm saying that there is no need for phase angle control for this application, and it has drawbacks (that I stated earlier in this thread), that can be avoided by using an SSR and PWM control instead.
 
Ah! Gotcha! Yes, phase angle control can be a problem...

That's what a cheap, poorly designed, light-dimmer control uses.

For others following along, this is what phase angle control looks like (this shows a full-wave rectified signal... but you should get the idea):

220px-Regulated_rectifier.gif


Where a LOW-Frequency PWM controller will control the number of full cycles of AC power that get through to the heater. For example if you set a 1Hz PWM controller to 10%, it will let 6 cycles through to the heater and block 54 cycles every second. At 50%, it will let 30 cycles through to the heater and block 30 cycles. etc...

(This stuff can make your brain hurt... especially if everybody's not on the same page!)
 
alphaomega said:
It might be, but again, it's not really(IMHO) a good solution.
A solid state relay and a ~1Hz PWM is the better choice.
Click to expand...

question for you... could I use one of my extra 21khz pwm dc controllers with say 24v going through it to control a standard ssr? of does it have to be 1hz for the ssr to react correctly?
 
The PWM frequency needs to be lower than the power line frequency, probably by a factor of 10 or more. If it's considerably higher, it's effectively always on!

When you trigger a thyristor, it turns on, and doesn't turn off again until the waveform crosses zero. It doesn't trigger on and off multiple times during each half of the cycle.
 
@jimdkc: Thank you!!!
Not only was that a nice rundown of the functional difference, but finally someone who *gets* it. I've been preaching avoidance of SSVR's for some time, but few listen. To the point I almost don't care anymore... Now, help spread the word! :)

The issue is that phase angle control, 'cuts up' each half period. That sharp 'cut' produces a lot of overtones, that are sent down the wires (that also act as antennas) and can interfere with a lot of other electronic stuff. As the power draw is high, the noise will also be powerful.

There are other applications where phase angle control is warranted, but ideally the circuit should then contain snubbing, to dampen the noise, something that is missing from cheap SSVR's as is would be cost prohibitive to include (and also, probably would depend on the load in use).

But, for controlling power to an element, there is no need for phase angle control. The time constant for the element alone is probably a few seconds at least.
SSR's (of the zero crossing variety, which is the "normal" ones) are nice in that they only switch on or off when the sine wave that is mains is at zero volts, thus producing very little interference. But for this application, even normal relay and on/off would be a better choice than SSVR in my opinion.

For using an SSR, you need a way to generate ~1Hz PWM. The Auber DSPR1 or EZBoil (already mentioned in the thread) are good options. If you are cheap, but can do some light soldering have a look at this thread or possibly just get something like this (eBay link) or like this (eBay link) (although, this latter one can only set output in steps of 10%, but that is probably good enough anyway, it instead 'wins' in that it is just a knob for control).
 
(Deep breath.... gets ready to jump in with the sharks...)

I use 2 2000w heat sticks, plugged into 2 separate gfi outlets, no controller or any of the other things with many more letters you've mentioned.

This makes 11 gallon batches with a 13-14 gallon boil in a 15.5gal kettle (not Keggle) perfectly. 5.5 gallon batches with 7-ish gallon boils you could use both elements to get to boil fast or just wait longer and use 1.

There's also a 1000w heatstick with a controller and timer if I want to heat strike water. Lately I've been deoxygenating with yeast and dextrose and not using that, but it worked great for dozens of batches.
 
alphaomega said:
@jimdkc: Thank you!!!
Not only was that a nice rundown of the functional difference, but finally someone who *gets* it. I've been preaching avoidance of SSVR's for some time, but few listen. To the point I almost don't care anymore... Now, help spread the word! :)
Click to expand...

Yeah... What you were getting at clicked in my brain when you mentioned phase angle control!

For using an SSR, you need a way to generate ~1Hz PWM. The Auber DSPR1 or EZBoil (already mentioned in the thread) are good options. If you are cheap, but can do some light soldering have a look at this thread or possibly just get something like this (eBay link) or like this (eBay link) (although, this latter one can only set output in steps of 10%, but that is probably good enough anyway, it instead 'wins' in that it is just a knob for control).
Click to expand...

I'd be tempted to build my own PWM controller from a 555 timer chip. (I worked a lot with 555 chips a long time ago, and I love them!) Here's a link to one that explains it pretty well:

A SIMPLE PWM CIRCUIT BASED ON THE 555 TIMER

Instead of feeding a MOSFET to control a motor, I'd feed the output of the 555 directly to the control terminals of a zero-crossing-switching SSR. If you use a 1MΩ pot for R1 and a 1.5µF capacitor for C1, the frequency would be about .96 Hz. The pot would adjust from 10% power to 90% power (You can have 100% power by adding a "Full Power" switch that turns the SSR on constantly.)
 
@jimdkc: The 555 is indeed a classic chip :) The thread I linked to (slow PWM LED hacking) IS a 555 based circuit, but it's improved. The 555 generate a sawtooth signal, which is fed to comparator, and it can therefore produce the full 0-100%. The 'hack' is simply to add capacitance to RC timing part to lower the frequency.
While it is fun to build your own, I highly recommend you check it out. Those LED dimmers are dirt cheap, the modification is super simple, and you'll end up with a very 'clean' result (well, you may a lot better than me, as my hacks usually end up as big mess o' wires). It just isn't worth the effort to build your own, unless your goal is not just to get it done, but to have "fun" building it.
 
Well, I do think that building circuits from scratch is fun!

But... I hadn't clicked through and seen just how inexpensive those controllers are! I ordered a couple of those to tinker with! No need to reinvent the wheel when those are just a couple bucks and change each!

And, I was about to suggest just paralleling the new capacitor in instead of trying to de-solder it and fry the SMT circuit board traces, but I read the whole thread and see that you had already suggested that!

:mug:
 
I don't think that would qualify as a PID (because it's not), but as the lid is mostly round, I'd call it the "Floppy disc controller".
Looks awsome. And nice job documenting it for posterity!
 
wilserbrewer said:
That looks impressive Floppy! I noticed that the "Flop-Pid" only reports temperature in fahrenheit to either the whole number or "surface of sun". Do you find this level of accuracy adequate for recipe repeatability and / or step mashing.
Click to expand...

My first prototype reported temperatures in Kelvin. This failed because trying to reach 373.15* seemed a little silly. Fahrenheit was the next popular choice. Repeatability and step mashing are not a problem with the Flop-PID. The infinite adjustability of this device guarantees repeatability (repeatability is not guaranteed)

alphaomega said:
I don't think that would qualify as a PID (because it's not), but as the lid is mostly round, I'd call it the "Floppy disc controller".
Looks awsome. And nice job documenting it for posterity!
Click to expand...

Common misconception you have there. The standard acronym of the Proportional Integral Derivative used by many brewers is often mistaken for my, more reliable, Positionable Interchangeable Dome.

If you have some time, I can tell you all about how I make my brew day easier with my RIMS (Rum In My Sarsaparilla) and my HERMS (Have Every Recipe on Memory Stick) helps with my ability to repeat recipes.

:tank:
 
@FloppyKnockers: You're right. I wasn't aware of that... (I hesitate to say less standard, so I'll go with up and coming) acronym.
I'd absolutly love to hear about all your innovative work, especially if it comes with the same 'better than norm' technical documentation. But maybe it would be better suited for a new thread, as this one is allready in a death spiral :)
 

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