Controllerless electric boil keggle

[conpewter]

I'm trying to think of a simple build for an electric 220v boil kettle. I'd want 5500W or more to get the pot boiling, but less than that to keep the boil going. My thought is to put in two elements, 3000W or so each. Then have a switch inline on one of the elements to turn it off during the boil.

I can find 3000W elements but I didn't see them in the limelife sections, those can withstand dry firing. Maybe do a 2500W and 3500W element, using the 3500W to keep the boil going.

Any feedback on this idea is appreciated.

 

[cruelkix]

I'm trying to think of a simple build for an electric 220v boil kettle. I'd want 5500W or more to get the pot boiling, but less than that to keep the boil going. My thought is to put in two elements, 3000W or so each. Then have a switch inline on one of the elements to turn it off during the boil.

I can find 3000W elements but I didn't see them in the limelife sections, those can withstand dry firing. Maybe do a 2500W and 3500W element, using the 3500W to keep the boil going.

Any feedback on this idea is appreciated.

From what ive seen so far with my electric kettle it is very interesting the amount of energy you need to maintain a boil. My system is self learning but ive seen my 5500w element get down to about 30% usage to maintain a boil. I guess what im saying is that I'm not sure how many watts you would need to maintain a boil, but I will say that if you have any variation in your batch size/insulation/outside temperature it will change. So I guess you better be ready for some vigorous boils and some possibilities of boil overs. I hope that helps. I think you are on the right track but it is very cheap to just get a PID and an SSR. Like $80... it might save you a lot of headaches. Check out The Pol's walkthrough on it.

 

[HarkinBanks]

I built my e-kettle with two 2K elements and I have found I need about 3750W to keep the boil where I want it and get a good boiloff for around a 7 gallon pre boil volume. The only way I can do this is with a PID on one of the elements. Your 3500W element would be a better choice if you don't want to use a controller.

 

[conpewter]

Hmm on my setup I can run at 50% or 60% on a 5500 W element and be just fine. Probably has a lot to do with kettle shape actually. I don't have boilovers though, foam control drops take care of that. It has been a while since I've done any 10-12 gallon boils though.

PID and SSR are nice, and I do like mine, but I'm looking for a way to build a more economical electric keggle, may not be possible.

 

[HarkinBanks]

Depends on how much of a boil you want and how much boiloff. I can run it with just 2K and get a decent boil but not enough boiloff to hit the numbers I want. I use a hop bag, so I want a roaring boil but not too much boiloff. I use an insulated 8 gallon SS NSF pot as my BK and get a 1.28 g boiloff at 3750W over 60 minutes.

 

[ScubaSteve]

Totally unrelated, but foam control rocks! I wish people would use it more often, if not for safety. Conpewter, what would you say your duty cycle was when you were doing 12 gallon boils?

 

[conpewter]

Totally unrelated, but foam control rocks! I wish people would use it more often, if not for safety. Conpewter, what would you say your duty cycle was when you were doing 12 gallon boils?

I don't remember what I ran it at back then, my 5-7 gallon boils normally run 50% but I've had it up in the 80's and 90's when I've had a fan on the wort to boil off extra. I'm thinking a set percentage just isn't going to work out well.

 

[cruelkix]

I don't remember what I ran it at back then, my 5-7 gallon boils normally run 50% but I've had it up in the 80's and 90's when I've had a fan on the wort to boil off extra. I'm thinking a set percentage just isn't going to work out well.

I feel like there are just too many variables that can effect the load requirements. hell even if you change the style of beer you are brewing, the load would change due to the SG change.

 

[GreenMonti]

Why can't these E-keggles be controlled with a dial like on a stove? I have a heater in my garage with a knob on it like that and it is a 3000 watt heater.

 

[HarkinBanks]

Why can't these E-keggles be controlled with a dial like on a stove? I have a heater in my garage with a knob on it like that and it is a 3000 watt heater.

They can, I control mine via a PID, basically a digital dial.

 

[DavidP]

Why can't these E-keggles be controlled with a dial like on a stove? I have a heater in my garage with a knob on it like that and it is a 3000 watt heater.

To get the "dial" control you can create an adjustable PWM circuit which will trigger an SSR. I'm unable to find the site but a guy has a good writeup on his setup which does just that.

 

[GreenMonti]

They can, I control mine via a PID, basically a digital dial.

Thanks for the responce. I was thinking of something more flinstone, like a dial. Is that possible? What about the bigger elements?

 

[GreenMonti]

To get the "dial" control you can create an adjustable PWM circuit which will trigger an SSR. I'm unable to find the site but a guy has a good writeup on his setup which does just that.

Seems like it should be more easy. Like I say I have a heater in my garage with a dial on it. Maybe I should pull the dial out and see who makes it.

 

[DavidP]

Seems like it should be more easy. Like I say I have a heater in my garage with a dial on it. Maybe I should pull the dial out and see who makes it.

An electric kitchen range uses a rheostat to control the voltage across the heating element. The problem here is that you'll have to find a very high power model to handle a 4000W+ element.

 

[GreenMonti]

This is the best I could do on mine. No name just some numbers.

 

[GreenMonti]

Googleing the numbers on top came up with honeywell. I went to this link. 25 bucks. For 50 bucks you can controll 2 3000 watt elements, this is a whole lot more easy to do then wire up a PID and the such. IMO
http://www.patriot-supply.com/products/showitem.cfm/6965

 

[Wade E]

You ca get a Ranco controller off Ebay for $49!

 

[The Pol]

You ca get a Ranco controller off Ebay for $49!

Those are only good to 120VAC 15-16A, arent they? A simple 2000W element would exceed those limits if that is the case.

120VAC at 16A? (1920W)
240VAC at 8A? (1920W)

Ranco's are also on/off controllers and do not control duty cycle. You can get a % output from a PWM, PID, Infinite Switch... but the Ranco would be a different story.

 

[conpewter]

Very interesting! I wonder if there is a similarly priced model that can control 5500 W (or if that one could..)

 

[GreenMonti]

What I posted is an infinite switch, yes?

 

[DavidP]

Found the PWM setup: http://home.chattanooga.net/~cdp/boilnew/boilnew.htm

Definitely would be a lot more complicated than a kitchen range knob but also much more efficient. In order to get 70% efficiency with a voltage divider you have to throw away 30% of your power.

 

[conpewter]

What I posted is an infinite switch, yes?

I believe infinite refers to it's adjust ability (basically it's analog, so you can have any percent of power between it's 22% and 100%) I'm sure you can't put an infinite amperage through it.

 

[conpewter]

Found the PWM setup: http://home.chattanooga.net/~cdp/boilnew/boilnew.htm

Definitely would be a lot more complicated than a kitchen range knob but also much more efficient. In order to get 70% efficiency with a voltage divider you have to throw away 30% of your power.

I'm not sure how much more efficient it would be, you are not throwing away 30% of the power in your example, you just don't use it.

The Infinite switch uses what is called a Bi-metal switch to control the switch action. The Bi-metal switch physically moves through the process of heating and cooling. This movement causes the main switch contacts to open and close, thereby, controlling the power applied to the heating elements. Rotating of the infinite switch changes the relationship of the "on" and "off" times or duty cycle. As the switch is rotated to a higher heat setting the main contacts remain closed for a longer period of time. Conversely, rotating the switch to a lower heat setting causes the main contacts to remain closed for a shorter period of time.


http://americanhvacparts.com/Mercha...ROD&Product_Code=INF2194110&Category_Code=ES6

 

[GreenMonti]

Found the PWM setup: http://home.chattanooga.net/~cdp/boilnew/boilnew.htm

Definitely would be a lot more complicated than a kitchen range knob but also much more efficient. In order to get 70% efficiency with a voltage divider you have to throw away 30% of your power.

See, not to be a PITA. I just don't want to learn all that. I guess I am lazy. I want to go electric but I don't want to mess with that.

I believe infinite refers to it's adjust ability (basically it's analog, so you can have any percent of power between it's 22% and 100%) I'm sure you can't put an infinite amperage through it.

No, I agree. You can't just send what ever amperage you want through it. It even says 15 amp on it. I asked cause I read infinet while doing the search. I guess what I was asking is, The unit I posted is one of a few different options? Simple, but good. Maybe not as efficent but will work just fine.

I know your thread is a controllerless......but this offers a more simple soultion after the other posts of variables.

 

[Brewmoor]

You can buy pre-built PWM circuits. Check on ebay. They always have cheap ones that should work. Wiring it to a SSR is not too much harder then wiring an element straight up to power.

Or you could just get crazy. The electrobrewer got me thinking last night. Get hydronic electric baseboard heaters. Hack one or two up and create a heat on demand system where the wort flows through the heaters. Maybe a rheostat would work then.

 

[The Pol]

See, not to be a PITA. I just don't want to learn all that. I guess I am lazy. I want to go electric but I don't want to mess with that.



No, I agree. You can't just send what ever amperage you want through it. It even says 15 amp on it. I asked cause I read infinet while doing the search. I guess what I was asking is, The unit I posted is one of a few different options? Simple, but good. Maybe not as efficent but will work just fine.
I know your thread is a controllerless......but this offers a more simple soultion after the other posts of variables.

Nevermind.....

 

[DavidP]

..infinite switch info..

Cool, I didn't know about these! I just assumed that ranges used big-ass rheostats.

 

[Boerderij_Kabouter]

I think the easiest thing would be to buy a PID and SSR. Jumper the thermo probe contacts on the PID, and use it in manual mode all the time. That would cost $80 including a box and be user friendly.

 

[freddyb]

Here's the solution I'm setting up:

Use the PWM motor controller here from Bakatronics: FK804 http://www.bakatronics.com/shop/item.aspx?itemid=383

It's a simple analog-controller $8 PMW kit. Change the capacitor C1 to 2.2uf to slow the frequency to 1Hz. Use C1=4.7uF for an even slower ~0.563Hz if you want. I checked it on the o-scope and 2.2uF looks fine for my needs. Connect the output to an SSR to control the heating element. No fancy controller/thermocouple setup necessary.

Find a nice looking knob at an electronics shop or build your own and you can make a pretty cool little dial for mounting on your control panel. Here are some examples: http://www.futurlec.com/SwKnob.shtml

 

[djt17]

Here's the solution I'm setting up:

Use the PWM motor controller here from Bakatronics: FK804 http://www.bakatronics.com/shop/item.aspx?itemid=383

It's a simple analog-controller $8 PMW kit. Change the capacitor C1 to 2.2uf to slow the frequency to 1Hz. Use C1=4.7uF for an even slower ~0.563Hz if you want. I checked it on the o-scope and 2.2uF looks fine for my needs. Connect the output to an SSR to control the heating element. No fancy controller/thermocouple setup necessary.

Find a nice looking knob at an electronics shop or build your own and you can make a pretty cool little dial for mounting on your control panel. Here are some examples: http://www.futurlec.com/SwKnob.shtml

Interesting; would a 12V DC power supply be needed to run this?