I've been reading this entire thread and am about ready to jump in the car and go buy the parts necessary to build one of these too, but have been hoping that somewhere in the thread someone would post detailed pictures of a completed unit, so I join runningweird in the request for these pics. This will be the first electronic thing I've ever built so I'm feeling the need for some "hand holding" here.
PWM..Show us How
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runningweird
Well-Known Member
okay so I got a few of the larger more easily identified pieces soldered in over breakfast...mmm fumes.
is this where the 2.2 capacitor is supposed to go? seems a bit big.
is this where the 2.2 capacitor is supposed to go? seems a bit big.
runningweird
Well-Known Member
with some help from bdsx from chat I put it all together,
this was suggested as the best position for the 2.2 uF capacitor
now to find a 12 v power supply and hook it up to a fan.
does anyone have a photo of this thing all hooked up in a panel?
this was suggested as the best position for the 2.2 uF capacitor
now to find a 12 v power supply and hook it up to a fan.
does anyone have a photo of this thing all hooked up in a panel?
Looks good.
I have to remember to place order for the last parts I need to build my homebrewed versions. RS doesn't seem to have the values I need in stock. Maybe I'll check the somewhat bigger RS in Big Rapids tonight and see what they got.
I have to remember to place order for the last parts I need to build my homebrewed versions. RS doesn't seem to have the values I need in stock. Maybe I'll check the somewhat bigger RS in Big Rapids tonight and see what they got.
I need some help with that circuitbee.com schematic... there seems to be a wire from the 12+, through the IC to the GRD....really? I have the parts and want to put this thing together and in the control box, but I don't care to make many mistakes doing it.
No such thing as a wire going 'through the IC to the GRD'. Those are Vcc and Gnd pins, for some reason, the software does not label them.
Islandboy85
Well-Known Member
Would these diodes work also? http://www.radioshack.com/product/index.jsp?productId=2036270&filterName=Type&filterValue=Diodes
lzrdkng14
Well-Known Member
I am looking at either building or buying a PWM like the bakatronics one. I am not sure if I can solder on a circuit board like that with a "regular" soldering iron. What do you guys use? Would this work: http://www.harborfreight.com/butane-pencil-torch-41169.html
Is anyone selling these boards pre assembled? I would probably be OK with paying a little bit more for one that is pre built....
Is anyone selling these boards pre assembled? I would probably be OK with paying a little bit more for one that is pre built....
lzrdkng14
Well-Known Member
Cool thanks, I was looking at that one too...any ideas where I should get the 2.2uF cap? Bakatronics doesnt sell them do they?
I don't know anything about Bakatronics, really. Radioshack sells capacitors, but I have no idea if they will specifically carry 2.2uF.
You might have to build it up out of other capacitors.
You might have to build it up out of other capacitors.
if you can stand the wait from china:
http://www.ebay.com/itm/New-10-Pcs-x2-2uF-35V105-Electrolytic-Capacitor-5x11-Radial-FREE-SHIPPING-SALE-/200678229081?pt=LH_DefaultDomain_0&hash=item2eb95ac459
edit: this says it ships from the USA:
http://www.ebay.com/itm/NEW-10-Pcs-...824?pt=LH_DefaultDomain_0&hash=item231afe3d58
edit: this says it ships from the USA:
http://www.ebay.com/itm/NEW-10-Pcs-...824?pt=LH_DefaultDomain_0&hash=item231afe3d58
runningweird
Well-Known Member
I bought the capacitor and the soldering iron(9 dollars I think) at Radio Shack.
this was pretty easy to do and my PWM is still going strong after quite a few batches.
this was pretty easy to do and my PWM is still going strong after quite a few batches.
juvinious
Well-Known Member
I have been reading through this post very good stuff as this is a great alternative to actually having a dedicated pid for the boil kettle element. I went ahead and did a quick search for PWM's on ebay and I found this bad boy: http://www.ebay.com/itm/New-40A-110V-220V-Power-Adjustable-Thyristor-Transform-3800W-PWM-Speed-Control-/260971972903?pt=LH_DefaultDomain_0&hash=item3cc3244927#ht_500wt_1180.
I was wondering if it would work instead of having to put one together from scratch and for the price you can't beat it. Any thoughts?
I was wondering if it would work instead of having to put one together from scratch and for the price you can't beat it. Any thoughts?
Heck, at that price you could set one up and not use an SSR - so long as you stayed under 3800W and 40A.
Would this work with 120v elements? I'd really like to have something this easy instead of building a PWM board and using an SSR.
pvtschultz
Well-Known Member
Wouldn't our Ohmic (resistive) heating elements be just that, a resistive load? I'm not seeing where the inductive load is coming from (ie an electrical motor with moving magnetic fields). I'm just a mechanical engineer so I might be missing the obvious, but I believe these heaters are just simple resistive loads.
heating elements are a pure resistive load.
that thing should work for a heating element size 3800W or less, I would think.
But I think his point was that the 3800W is the limiter for an element and not the 40A.
that thing should work for a heating element size 3800W or less, I would think.
But I think his point was that the 3800W is the limiter for an element and not the 40A.
pvtshultz you are absolutely right heaters are a resistive load not an inductive one.
Walker thank you for putting my thoughts into words that actually make sense.
I have now deleted the post in embarrassment and will no longer attempt to post while distracted by the beer in my hand. I will finish the beer first.
Walker thank you for putting my thoughts into words that actually make sense.
I have now deleted the post in embarrassment and will no longer attempt to post while distracted by the beer in my hand. I will finish the beer first.
juvinious
Well-Known Member
Afaics it should as it states:
Aside from that, I assume from the above conversation that this unit will not require an SSR to do the off/on switching.
I'm going to go ahead and place an order for one. I'll give it a go and see what the deal is.
lzrdkng14
Well-Known Member
I stumbled across this today: http://www.harborfreight.com/router-speed-control-43060.html
Wondering if it would work for 120v (15 amp) set ups. I am building a 220v (30 amp) - so its not really relevant for me, but thought I would share it...
Wondering if it would work for 120v (15 amp) set ups. I am building a 220v (30 amp) - so its not really relevant for me, but thought I would share it...
As I understand it a BK heating element doesn't require anything more complex than a 555 timer and a couple of cheap components and a POT. It should work for 120V or 220V.
Am I missing something?
Am I missing something?
You need a 555 timer, a couple cheap components, and then an SSR.
That thyristor works as is. no SSR needed and no assembly required. And it will cost about the same as the PWM+SSR when all is said and done. I
The only drawback is the 3800W limitation. A PWM can drive whatever SSR you want, so the wattage is pretty much unlimited.
but if you are doing 3000W or 2000W or 1500W... this looks like a pretty convenient option.
EDIT: just realized that you might have been talking about the router controller. That restricts you further down to 1500W, but is very conveniently packaged. I have a friend who could put a couple of these to use immediately because he has two 1500W elements in his kettle with no controls of any sort at the moment.
juvinious
Well-Known Member
Cool you wrapped up all the questions with a little more detail thanks again! 
I looked at the lead time on that thyristor and it's about 2-3 weeks. While it's convenient the 3800W has me wanting to put together a pwm to have the flexibility of an SSR so I haven't ordered it yet.
I looked at the lead time on that thyristor and it's about 2-3 weeks. While it's convenient the 3800W has me wanting to put together a pwm to have the flexibility of an SSR so I haven't ordered it yet.
Cool you wrapped up all the questions with a little more detail thanks again!
There is another option out there. I can't remember the name/acronym attached to it, but it looks like an SSR. On the control side, you directly wire a in pot. Twisting the pot messes with the angle of phase of the AC signal and gives you an effective lower voltage on the output.
The are more expensive than a PWM+SSR or the thyristor, but they have the ability to handle a higher load than the thyristor and assembly is minimal.
This ring a bell with anyone?
after trying to locate the mysterious thing I was talking about, I think that the thyristor is the same thing, just called by a different name and packaged up differently that what I had in mind.
The thing (I think) that I was trying to remember was called an SCR.
Coincidentally, I found lots of those thyristors on ebay, and some for basically nothing. Current auctions for $0.01 with free shipping and stuff like that.
What surprised me even more than that was the actual size of the thing. That link above shows a pic, but there is nothing in the pic to establish scale (is it the size of an ice cube or the size of a lay-z-boy?)
I found this listing which gives you a better idea how big that thing is:
http://www.ebay.com/itm/Light-Speed...169?pt=LH_DefaultDomain_0&hash=item3371d7c4f9
And here is a cheaper one:
http://www.ebay.com/itm/3800W-SCR-E...395?pt=LH_DefaultDomain_0&hash=item27bfb40c2b
The thing (I think) that I was trying to remember was called an SCR.
Coincidentally, I found lots of those thyristors on ebay, and some for basically nothing. Current auctions for $0.01 with free shipping and stuff like that.
What surprised me even more than that was the actual size of the thing. That link above shows a pic, but there is nothing in the pic to establish scale (is it the size of an ice cube or the size of a lay-z-boy?)
I found this listing which gives you a better idea how big that thing is:
http://www.ebay.com/itm/Light-Speed...169?pt=LH_DefaultDomain_0&hash=item3371d7c4f9
And here is a cheaper one:
http://www.ebay.com/itm/3800W-SCR-E...395?pt=LH_DefaultDomain_0&hash=item27bfb40c2b
Islandboy85
Well-Known Member
Islandboy85 said:
Anyone?
Junkster
Well-Known Member
Is this what you're thinking of?
https://www.homebrewtalk.com/f170/variable-resistance-ssr-boil-control-310622/
Ah, yes. I already have an SSR and it slipped my mind.
I need to build that circuit soon since my spa panel is shipping to me as we speak and I need to test the element and get working on my BK.
blakeseven
Well-Known Member
I just finished my pwm control panel. This is a temp setup as I plan to go herms controlled by a bcs once funds become available.
Spa panel with 4 prong 50 amp dryer cord
Control panel for BIAB keggle
Inside front panel of control. note the PWM on the door.
Wiring for ssr note outlet for wall wart in lower right
Electric brew keggle
Hope this helps
I have tested with water only. Great control over the boil. I will be brewing a 10 gal blue moon clone later Today. Wish me luck.
Ben
Spa panel with 4 prong 50 amp dryer cord
Control panel for BIAB keggle
Inside front panel of control. note the PWM on the door.
Wiring for ssr note outlet for wall wart in lower right
Electric brew keggle
Hope this helps
I have tested with water only. Great control over the boil. I will be brewing a 10 gal blue moon clone later Today. Wish me luck.
Ben
blakeseven
Well-Known Member
Here is the panel at work
Panel active
Rolling boil with ic ready for cool down
Panel active
Rolling boil with ic ready for cool down
davefj40
Well-Known Member
will this cap work?
GregKelley
Well-Known Member
It will but your cycle time will be much faster so your SSR will switch on and off more often, possibly wearing it out.
GregKelley
Well-Known Member
I built my PWM using the information in this post. Instead of the 33μF cap, I'm using a 22 (because that was what I found).
When I connect everything up and I put my voltmeter on the output, I get 0v when the pot is turned all the way counterclockwise. Great, power is out. However, when I turn it all the way clockwise, I see my voltmeter cycle between 5v and 0v. I thought I should get 5v the entire time. Am I wrong?
When I connect everything up and I put my voltmeter on the output, I get 0v when the pot is turned all the way counterclockwise. Great, power is out. However, when I turn it all the way clockwise, I see my voltmeter cycle between 5v and 0v. I thought I should get 5v the entire time. Am I wrong?
davefj40
Well-Known Member
GregKelley said:
So is this not the right cap talked about earlier?
GregKelley
Well-Known Member
There are 2 caps that are used. I highly recommend reading this post. The 0.01 cap should not be changed. The 33 cap affects the cycle as is written in the drawing.
davefj40
Well-Known Member
i used the Bakatronics kit were someone mentioned putting the 2.2 cap in. have not used to live yet but it seems to be working as far as watching the light come on and off.
