MY SUPER SIMPLE CONTROLLER

[shadylane]

I'm glad it worked for you bronctoad, I'm always happy to hear when one of my threads helps someone. It's actually kind of funny how simple a controller can be once you build one.

Thanks Cranky
I think of a controller as a switch that's being turned on and off real fast.
The timing of the on/off is what control's the power.

[cranky]

I'm glad it worked for you bronctoad, I'm always happy to hear when one of my threads helps someone. It's actually kind of funny how simple a controller can be once you build one.

Thanks Cranky
I think of a controller as a switch that's being turned on and off real fast.
The timing of the on/off is what control's the power.

Actually I think the people who really need thanked are all the people who helped me understand how all this stuff works and continue to help even in this thread. All I did was try to make a thread that can help someone with as simple understanding of this stuff as myself build a controller.

[rcazparts]

Built myself a controller. Should have done this from day one. So much easier than propane cooker. Heat sink is in box, but going to need a fan. Box was getting too warm. Thinking I could mount the heat sink on the outside, but would just burn myself on it.

The box needed a load on it for everything to function properly. Without the heating element plugged in, making adjustments went from 30v to 110v instantly. Once the load was on it, the adjustment worked as expected. Probably shared somewhere in this thread, but sharing what I learned.

Thanks to everyone for sharing all the great advice!

[NormandieStill]

Built myself a controller.

How is the switch connected? If you're switching the load side then you should check the current rating. I have some similar ones that are rated to 10A (From memory) which will be good only up to around 1.1kW at 110v!

[rcazparts]

The switch is 20a, 240v, double throw, double pole. I am using 110v, so it should be fine.

[NormandieStill]

The switch is 20a, 240v, double throw, double pole. I am using 110v, so it should be fine.

Then it can handle a maximum element size of 2.2kW. And you've got no margin for error.

What does the current reading say when your knob is turned all the way up?

[rcazparts]

Actually, 120v 20amp switch. Just looked it up.
Element is 120v 1650 watt.

[john_bud]

Thanks to all for this thread. The parts are all out of date on amazon, not surprising. But i found they have a "kit" with the SS relay, variable resistance control and even a knob. All for like 15 bux usd. I ordered it and will see how it does on an electric device. My device is thermally controlled, but on 100% when below temp and 0% at temp. The plan is to dial it so it's always on, then plug it into an outlet with adjustable amount of power with the SS relay.

Wish me luck

[still_stirrin]

… Wish me luck

Hey JB, I suggest getting a fan to blow over the heat sink when running. That SSR will put out a lot of heat.

Also, be sure to use electrical heat sink compound when mounting the relay to the heat sink. It’ll help keep the “smoke” inside the relay.

Good luck.
ss

[cranky]

I can't believe it's been more than 9 years since I made that first post. Most of that time I've had a complete spare set of parts sitting on my desk to replace whatever went bad. Maybe I need to do more stilling It's not like I haven't run it hard when I do run

[JollyPirate]

Hey folks! So, first of all, thank you cranky and all the others on this thread... this has been immensely helpful as I've put together the final piece for my still (I've moved soooo slowly). I've been looking forward to this part because, admittedly, I know very little about wiring and electrical work and building the still has been an exercise in building some of those skills. It's been fun!

Here's the problem, as you can see from my uploaded picture, I'm getting no amps . Volts are tracking and adjustable with my ssr/potentiometer, but I've got no amps and no heat on the element. My suspicion is that I have a bad element (I cut some corners, bought a heavily discounted one about a year ago and my three year old has been rough with it a couple of times as it sat in my garage).

Before I shell out $60 for a new element, would you kind folks offer any troubleshooting advice to a newbie? My wiring looks solid, but I could be missing something.

To add some extra data, a separate breaker (not the 40 amp breaker I have my element on but the 20amp one I have my flan plugged into) tripped when I turned it up high.

[Yummyrum]

LOL , as an old TV tech I do like a good fault find
Do you have a multimeter ?
If you do , there are a couple of quick tests .

Iff’n you don’t can you take some pics of the element connections and the wiring inside the box .

[quadra]

So... lets see the wireing..... and am I reading that wrong or are you saying there are two different power sources? Seperate 40A and 15A in to the same box?
I only see one power switch...? Either way... if your fan circuit tripped when you turned up the heater the problem is probably not your element..

[JollyPirate]

Yep, Quendra, that's correct. I've got the 240v double pole switch connected to the outlet we use for our dryer (on a 40A breaker) and I've plugged the fan into a separate 110v outlet (on a 20A) that's nearby. I've attached a picture of the inside of the box for reference (I don't have on hand a pic of the inside of the lid where the switch and potentiometer and voltage meter are located, I can hopefully snag one this evening).

And YummyRum I do have a multimeter! Tell me about these "quick tests" of which you speak.

[greggn]

I've got the 240v double pole switch connected to the outlet we use for our dryer (on a 40A breaker)

What is "Hot(2) to pot from switch" ? Why is the potentiometer inline with the switch ?

[JollyPirate]

Greggn, the potentiometer is wired to the ssr which is connected to the the first hot leg (red wire) between the switch and the element. The switch is there so I can easily shut off power to the whole box without having to manually flip the breaker. "Hot (2) to pot from switch" is the second hot leg (black wire) that goes directly from the double pole switch to the element (or more specifically, to the outlet I wired to the side of the box and plug my element into).

Thanks for your patience, my nomenclature may be off in describing these... again, beyond switching out the occasional outlet, this is my first electrical rodeo lol

[Yummyrum]

And YummyRum I do have a multimeter! Tell me about these "quick tests" of which you speak.

You say you suspect the element is faulty . The safest test is to measure the resistance of the element .
These test must be done with the controller unplugged from the wall .

Switch multimeter to the lowest Ohms range ( it’s usually 0-200 on 99.9% of meters )
Always touch the leads together first and confirm you have a short circuit reading close to 0 ohms ( less tham 1 ohm is typical)

Now , Connect the probes to the element terminals . The elements resistance will vary depending on what wattage you have and what voltage it is designed for.
A 5500W 240v element will be 10ohms
A 2000w 240v element will be closer to 30ohms

So you can expect a resistance roughly in this range if your element is OK .

If your element is not heating then it is usually that it’s internal wire has broken . The resistance will be almost infinitely high .

So if the element is not showing a resistance , it is the problem .

If the element does measure OK , then the next thing to assume is that the voltage from the controller is not reaching it .
We now need to check the cable from the controller to the element .
You should know which wires these are . Again measure the resistance on these two wires . This is testing the resistance of the circuit down one wire to the element , through it and back up the other wire .
The resistance should be almost exactly the same as the resistance of the element plus maybe a fraction of an ohm more due to the cable resistance .

If the cable is OK as well , you should get a reading in the 10-30ohm range as before .
If there is a brake or bad connection , the resistance reading will be close to infinite resistance . ( on the 200ohm range that will show as over-range )

So if the reading is showing an open circuit you’ll need to carefully check your connections until you get a good measurement and hopefully problem solved .

I can’t offer any more advise until you show more pics of your wiring . There is a lot missing in that pic you showed . For example , does the wire to the element connect directly to the SSVR terminal or is there another connector or switch in between .

What I did see that worries me a bit ( although it has nothing to do with your fault) is that you appear to have used data cable to connect the pot to the SSVR .

Data cable insulation is not rated to handle mains voltage . The Pot terminals are at mains voltage and subsequently need to be wired with suitably rated wire .

[quadra]

Take that red wire off terminal 1 before you kill yourself.

The SSR needs a variable potentiometer.... there is no need for power to the potentiometer.
The feeds to the heating element are not called pot ... because the " pot " in electronic control is always a potentiometer. Call it element, load or heater. Right now you have a ground path through your kettle or element that can kill you by just touching the shaft of your potentiometer and the boiler at the same time... it will not stop electrocuting you until that little red wire or you glow red and become more than 40 Amps resistive... or burn up..

That does not explain why the 15 Amp circuit tripped. Where is the fan wireing and how does it connect to this?

[Yummyrum]

Quadra , it sure is hard to figure out without the full picture of the wiring but I think that skinny red wire is the Voltage input to the Digital meter . Jolly Pirate does say that his meter is displaying a change in voltage as he adjust pot , so I assume that is the point of connection .

But , that highlights another potential problem which again has nothing to do with the problem at hand .

Jolly Pirate , alas those Chinese meters don’t like to be connected to the output of an SSVR .
Sure , they show the voltage , but they also blow up very quickly . Especially if the dial is down low . It’s just a quirk of them when running on a phase controller .

Most filk here have realised that you need to connect the voltage input to the input of the SSVR … not the output .

Sure , the displayed voltage will not change when you adjust the knob , but the smoke will stay in the meter . Just use the current reading as your guide .

[quadra]

That would be better... but it sounds like the two circuits are common or sharing a neutral somehow.

[Yummyrum]

Yeah that 110 v circuit breaker operating when Pot turned up is a bit alarming for sure .

In a land where we only have 240v as an option , it surprises me when folk jump back to using 110/120 v for things like fans etc . To me , it makes more sense just to use a 240v fan and keep 110v out of it…. and the wiring safe and simple .

An honest wiring diagram and more pics will surely help .

[quadra]

And we still have one power leg for the meter not accounted for.... wondering if the meter is powered from the other circuit?

[JollyPirate]

Take that red wire off terminal 1 before you kill yourself.

The red wire is connected to the voltage meter. Not the potentiometer.

[JollyPirate]

But , that highlights another potential problem which again has nothing to do with the problem at hand .

Many thanks! I remember making a mental note of that when reading through this thread but, regrettably, not a physical note lol. I’ll move it.

[JollyPirate]

Yeah that 110 v circuit breaker operating when Pot turned up is a bit alarming for sure .

I’ve attached a diagram of my wiring. One thing that’s odd about my switch is that the line and load are opposite where they typically are (I dunno maybe it’s common to have load on the bottom sometime, I’ve never seen it before).

The fan is on a separate circuit because I really didn’t want to wire a 110v outlet from the neutral on the 220v when I have another one nearby. The fan is mounted on the box exterior and there is no overlap of wiring

[JollyPirate]

You say you suspect the element is faulty . The safest test is to measure the resistance of the element .
These test must be done with the controller unplugged from the wall .

I think we have a winner, folks. The multimeter shows zero resistance on the element.

I took the plastic part off of the element to take a close look at the wiring below the connections and, sure enough, we have a broken element connection (if I’d used my ears, I could have heard it rattle).

Thanks, Yummyrum for walking me through it. My dad passed away last year and I’ve always relied on him for knowhow so it’s helpful to have some extra guidance.

[Yummyrum]

Glad you sussed it out .

Just a small point , no resistance and Zero resistance are actually the opersite of each other despite the english language typically suggesting that if you have none , you have zero

A resistance measurement of Zero ohms is normally what we call a Short Circuit whereas , no resistance reading is what we would call an Open circuit .
I believe this is what you meant .

[quadra]

Nice! Yummy your bench time shows.. that schematic diagram makes WAY more sense
Jolly, if your dryer connection is a 4 pin plug you have a neutral and ground on that same source and can pull your 120v from a single hot leg to neutral and keep it all on a single plug/ breaker... this is a better practice than pulling 120 and 240 into the same box.

[john_bud]

… Wish me luck

Hey JB, I suggest getting a fan to blow over the heat sink when running. That SSR will put out a lot of heat.

Also, be sure to use electrical heat sink compound when mounting the relay to the heat sink. It’ll help keep the “smoke” inside the relay.

Good luck.
ss

I "finally" made the time to assemble the parts. A leftover plastic junction box for transitioning underground wires to a house was used. (Not ideal, but it was free so.. ) ordered an amazon 120v 100mm fan to keep things cool as suggested. Then added a switch to turn it on and off as well. Had to make a fixture out of a scrap of 1"x1/8" flat to mount the fan. Used the vice, torch, hammer and beat it into shape. Then discovered i really suck at optimizing internal spaces.

Seems pretty easy to arrange everything... until you cut the holes and try to fit it all together! Then realizing had it moved a 1/4" this way or that way it wouldn't have been such a squeeze. Sigh... oh well. It did all fit, but was a struggle.

End result is the ability to reduce power from 100% down to zero. It works to accomplish that, so all is good.

Thanks to HD for the idea and guidance!

[Steve Broady]

The fan is on a separate circuit because I really didn’t want to wire a 110v outlet from the neutral on the 220v when I have another one nearby.

You might want to consider using a fan rated for the full voltage. This is the one I used, and it works quite well on both 120V and 240V
https://a.co/d/3RRooVf

Also, regarding that meter, it has been pointed out that they don’t like being in the output side of things. It looks like you’re using one similar to mine, though not identical. The problem is that they use the voltage input both to power the circuit and for the meter input. It is possible to open them up and separate the power and meter circuits. Connect the power side to the line, and the meter to the load. It’s not a difficult task, but it might require a little electronics knowledge unless you can find a tutorial on your specific meter. Once done, you can accurately measure voltage all the way down to zero without worrying about frying the meter.