My 220/240v 10000w SCR based controller build & parts list

[Nunyo]

Over the last two years, I have spent countless hours lurking and reading here. I have learned so much from other members by reading the various threads that I figured I wound contribute/give back where I could and this thread is a perfect place for my to contribute and hopefully help others like the many threads here have done for me.

I opted to build my own controller to run a single 220/240v 5500w heating element in my boiler. After running this controller several times now, I am very happy with how it works and feel it’s worthy of sharing with you. This should be especially helpful for people who are considering building their own controller since I have all the parts listed and am including some basic instructions.

I will note that I am not an electrician but the wiring is very straight forward. I did a lot of reading here before taking on this endeavor which insured my success. Since 220v is essentially a pair of 110v hots, I was able to wire up a 220v outlet in my garage to run this thing by adding a dual pole 30amp breaker to my sub panel and then an outlet box with a L6-30R receptacle.

In my controller, the power input (two hot leads) from the wall goes directly to the a 240v two pole 30 amp 220v circuit breaker in my controller box which serves as the ON/OFF switch for my controller. I used 10 gauge wiring for everything. The 10,0000w SCR relay controller setup I used was clearly marked for the in/out hot leads and the two hot wires on the circuit breaker connected directly to the two inputs on the SCR controller. The power input for the digital power monitor connected to the hot inputs on the circuit breaker as well. The monitor lights up as soon as the controller is plugged into to wall. The two hot outputs for the SCR controller goes to an L6-30R receptical on the NMEA controller box. I used a 220v fan which connected directly to the output on the Circuit breaker inside my controller so the fan turns on as soon as I switch the power on. The power monitor has a loop that goes over one of the hot leads from the SCR’s output. This is how the monitor determines the current output from the SCR.

I’ve attached photos of my build as well as a wiring diagram for the same type of SCR control interface. This wiring diagram was found on this forum and shared by another member. The only thing that isn’t included in the parts list below is a medical IV cart that I picked up used on Craigslist so I had a portable solution for mounting my controller. You can see it in one of the photos below.

These are a few threads that were instrumental for me when considering my parts list and wiring.

viewtopic.php?f=85&t=62655

viewtopic.php?f=85&t=44557

viewtopic.php?f=2&t=43456



Here is a breakdown of all the parts. I could have gone much more simple but I do like to complicate things.

I used this SCR controller. I bought 2 so I have a spare. I chose this type of controller for a couple reasons. First was the success of others who documented their builds here. 2nd was because it is rated for a much higher wattage than I was planning on using it for which means that it’s life should be extended since it will never be run anywhere near full capacity.
https://www.ebay.com/itm/AC110V-220V-10 ... 3432913042" onclick="window.open(this.href);return false;" rel="nofollow

This dial face for the above controller. This wasn't needed but i thought it added a finished touch to the enclosure while also giving me a visual point of reference on for the potentiometer that controls the power output.
https://www.amazon.com/gp/product/B01M9GZIC1" onclick="window.open(this.href);return false;" rel="nofollow

This NMEA enclosure. I could have gone cheaper but I wanted one that was rugged with plenty of room inside:
tps://www.amazon.com/gp/product/B00OG1X7K4" onclick="window.open(this.href);return false;" rel="nofollow

I used this circuit breaker as the power switch. I could have used a simple 220v 30a wall type switch but I wanted something a bit more robust. This is a rail mount circuit breaker which allowed me to firmly mount the breaker switch in my controller:
https://www.amazon.com/gp/product/B013SWPSY4/" onclick="window.open(this.href);return false;" rel="nofollow

These are the rails to mount the above breaker in the box. I cut the rail to fit the box and used standoffs and long screws to mount the rail so the face of the breaker would stick out through the face of the enclosure.
https://www.amazon.com/gp/product/B0159JLOCE" onclick="window.open(this.href);return false;" rel="nofollow

This digital amp/volt meter
https://www.amazon.com/gp/product/B00YY1KOHA" onclick="window.open(this.href);return false;" rel="nofollow

This 30amp L6 30R and L6-30P outlet and plug. I bought a couple of these so I had an outlet for my wall and for my controller box.
https://www.ebay.com/itm/30-Amp-250-Vol ... 3309669606" onclick="window.open(this.href);return false;" rel="nofollow

This 220/240v fan for keeping the controller enclosure nice and cool.
https://www.ebay.com/itm/220V-240V-8cm- ... 2756981482" onclick="window.open(this.href);return false;" rel="nofollow

These fan filters for keeping dust out of the enclosure. One went on the intake side and I used a standard fan grill over the fan side which pushes out.
https://www.amazon.com/gp/product/B00315C03G/" onclick="window.open(this.href);return false;" rel="nofollow

And finally, this Dernord 5500w tri clamp heater element that has a built in L6-30P plug connection on it. It made it nice and easy to disconnect the power from the heater while leaving the heater in the boiler. I see the price has jumped up about $40 between the time I bought mine and now so if you are looking to save some money, there are lots of other options that are much less but don’t have the built in L6-30 connector.
https://www.amazon.com/gp/product/B075KHLJ69/" onclick="window.open(this.href);return false;" rel="nofollow

[MtRainier]

This is great, thanks for posting the whole list. Looks exactly like what I'd like to build to scale up and go electric.

What boiler are you using? I'm getting a 16G from Mile Hi and wondering if that heating element you got will fit. It seems like it will since the amazon description says it is 350mm long which should be 13.75 inches and the boiler is 16" diameter.

[MtRainier]

So I decided to try to save a bunch and connect a cable right to the element rather than using the one with a plug you posted. It is hard to screw the 10ga stranded SOOW wire to the little terminals. Harder than screwing them into a socket like you did.

Now I see the logic of getting the model with the L6-30p connection.

[Nunyo]

This is great, thanks for posting the whole list. Looks exactly like what I'd like to build to scale up and go electric.

What boiler are you using? I'm getting a 16G from Mile Hi and wondering if that heating element you got will fit. It seems like it will since the amazon description says it is 350mm long which should be 13.75 inches and the boiler is 16" diameter.

Sorry for the late reply. The boiler is a 16 gallon one from Mile High.

[MtRainier]

Thanks.

I built pretty close to your controller build. It works great and was easy to put together.

[Bombo80]

This is exactly what I need to build. I was going to not have any monitor, but it looks so nice, I will add it to the build. Also the SCR controller I am looking at has a built in fan, but after looking at your build, I can see the exhaust fan will be a great addition, plus it will help keep things cooler inside the control box.

[82Winger]

Greetings. I built a controller almost exactly like the one mentioned. I have used it over the past year with great success, but yesterday it burned a batch on me. I was stripping a 3 segment run of All-grain. The first two 12 gallon runs went smooth but when I squeezed out the last of my grains and ran them it overheated. The product coming out smelled burned and when I removed the rugs and towel cover from around my keg, it was burnt/stuck to the outside. I removed the cover on the controller and everything looks ok. Did my SCR go bad? How can I check the output? Voltmeter/ Ohmeter? I'm sorry but electronics are not one of my strong suits. What sucks the most is that this was my first attempt at this recipe and to get this far and it go bad. The Mrs. was actually really wanting to try it. She was crazy about the aroma.
Thank you very much.

[Oldvine Zin]

Without knowing all the details of your setup and wash I would guess that it wasn't a controller issue, more like an issue with straining. Solids on your element caused a scorch


Be safe and read read and read

OVZ

[MtRainier]

Any way I can think of to diagnose would be done while under power and wouldn’t be safe to recommend to someone who confesses to be an electrical novice. 240v is no joke. Do you have a local friend who is comfortable around electronics and AC power to take a look?

[sambedded]

Did my SCR go bad? How can I check the output? Voltmeter/ Ohmeter? I'm sorry but electronics are not one of my strong suits.

Yes it may happens. Due to overheating triac inside your controller can kind of "melt" inside and then it acts just a piece of wire. No regulation at all.
One way is just connect voltmeter in parallel with your heating element and measure a voltage. Second way is take one 240V incandescence light bulb, or 2 identical 120V incandescence light bulb connected in series. Just plug it to your controller instead of heater. So you can visually observe if they are dimming or not..

[dirtyhands0321]

Hello Nunyo, excellent post and set up! I want to build a similar set up as you have but just have a question about the wiring of the heating element. I want to place a 1.5 inch sanitary 220 volt heater to my boiler, but on amazon, in North America we use two legs of 110 to make the 220, but in China where these elements come from as of most of the world, they use one leg of 230 with another leg for neutral and one for ground. So I assume with your setup you applied two legs of 110 to the element along with a ground (assuming your in North America) and had no adverse side effects?! Thanks in advance!

[Oldvine Zin]

Hey dirtyhands...
With these ssr's you only have to control one hot leg of your power = so in the USA just one of your hot legs needs to go through the controller the other direct.
If you are still unsure please ask again.
Be safe
OVZ

[charlie2K]

I have the controller hooked to my keg and full of water.....how can I test my controller? It has one leg going through it and one leg directly to my 5500 watt element. When put the volt meter on the leg being controlled no change in volts as I turn the dial.....is it not working then?

[sambedded]

I have the controller hooked to my keg and full of water.....how can I test my controller? It has one leg going through it and one leg directly to my 5500 watt element. When put the volt meter on the leg being controlled no change in volts as I turn the dial.....is it not working then?

To check SSR with voltmeter you need to connect some load - heating element, light bulb or something else.

[rubelstrudel]

According to that wiring diagram you're running all the power through the ampmeter module.... But you have wired that metering module according to the wiring on the back of the module, not like it says on that wiring diagram in the picture, eh?

You can't run power through that meter module.

[sambedded]

According to that wiring diagram you're running all the power through the ampmeter module.... But you have wired that metering module according to the wiring on the back of the module, not like it says on that wiring diagram in the picture, eh?

You can't run power through that meter module.

Why not? It has embedded shunt. So you should run power through a meter to read an Amps.

[rubelstrudel]

Why not? It has embedded shunt. So you should run power through a meter to read an Amps.

Not that meter. There's an induction coil on those two little wires that goes around the load wire to measure current. And two wires across the load to feed and measure voltage.

[jimmayhugh]

This is just my opinion, but I've got a one of these units, and I'm of the opinion that it's BADLY designed as far as the heat dissipation of the unit while operating under load. The heat sink is much too small, and the cooling air flow is terrible.

I've replaced the heatsink with one that's roughly 2-3 times the overall size of the OEM version.

My other concern is that the traces on the board are not capable of handling a sustained maximum load without de-laminating.

I have instead made my own units, using this heatsink, and this SSR kit.

While it may cost a little more, I can run this at a sustained 240vac at 22amps outside in the summer in Las Vegas with the heatsink barely warm to the touch, all without a cooling fan.

[rubelstrudel]

I agree with Jimmay. That is essentially making the same equipment, only with much better components and actual safety margins at fractionally higher cost.

[MtRainier]

Stilldragon sells a kit that includes a pot and a variable speed SSR with an enclosure and feet for less than you can easily buy the parts individually. Add one of those induction coil meters from amazon (which I've used twice and they seem to work well) and you got a nice controller.

[Oldvine Zin]

Yea the Stilldragon kits are a good value if you value your time for shopping for all the parts, plus you would be supporting a member of this forum. I also agree with Jimmay with that ssr, it's the one I use and have never had any issues with it. I use this inexpensive heatsink and it works great.

be safe
OVZ

[OtisT]

Stilldragon sells a kit that includes a pot and a variable speed SSR with an enclosure and feet for less than you can easily buy the parts individually. Add one of those induction coil meters from amazon (which I've used twice and they seem to work well) and you got a nice controller.

+1 on the still dragon kit. Mine has worked great for over a year. I did buy and add a second potentiometer for fine resolution power tuning. I find the fine tuning dial useful for tuning really low boils, like when pulling foreshots slow on the pot still.

I have bought two of those induction coil digital meters everyone else uses, and both of mine were shit. The end where the wires come in gets super hot and the LED display blacks out as it heats up. After two fails I am going old school and planning to add a simple analog AMP meter.

Otis

[rubelstrudel]

These simple induction coil amp-meters normally specify that they work in the range 80-240v AC. And the wires that measure voltage also draw power to run the meter. If I had run my load current at a fixed voltage, that would be no problem, but I frequently use voltages below 80V, and not a nice sine wave either, a very chopped up power. So far I have not understood how that little meter could ever measure anything acurately when the feed power is so variable, and so dirty.

I have toyed with the idea of just putting the feed/voltage vires on the power input, steady 220v side. But I don't know if it will be able to measure the current going through the induction coil at varying voltage then.

After all, the oldfashioned amp-meter is just an induction coil that to, just put inside the instrument. But maybe you can get better quality measurements with a bit of analog signal smearing.

[MtRainier]

I've used my digital induction meter many times so far and nothing has happened, but I could believe there would be long term issues. I put a big honking computer fan blowing into the controller case with air holes drilled in the case to keep everything cool, so maybe that helps. I also keep the controller box well away from where any alcohol vapor could be coming out even though that shouldn't happen unless I forgot to turn on the condenser cooling or something.

Rubel, how do you have voltages below 80V frequently? Are you running a rheostat before your controller to drop the voltage or something?

When I wired up my controller I put the power supply wires for the little power meter before the SCR, in parallel with the two hots in to the SCR so it sees a steady 240V of power, not in series with the load or after the SCR chops up the sine wave. I put the induction coil around one output wire coming out of the SCR. It doesn't use the input wires for the reading of the output power through the coil. It works very well that way. I can watch the power on my 5500W heater vary across the entire range. I advise you to do more than just "toy with" that idea.

[rubelstrudel]

Ah MtRainier,

the wiring diagram on the meters says to put the voltage/feed for the meter paralell with the load. And if you want to see the voltage of your output, that's where you need to put the wires. But if the meter shows the correct amp even thought the volts in the output is different from the volts the meter is measuring, then that's fine to.

I have a thyristor regulator bought from distillarius on ali, rated for 10KVA. But I am gathering parts to build my own box with a resistor controlled SSR and some serious heatsinks, blinkenlichten and sensors.

[MtRainier]

The voltage of the output doesn’t change. It’s 240VAC all the time, so the meter doesn’t need to be after the controller to measure it. The power controller chops up the sine wave so that you get less than the full currrent going through the element, but you are still running it at 240VAC, you are just missing part of each cycle.

The wiring diagram is right in that you are putting it in parallel with the load. You should do that. Just do it before the controller which modifies the sine wave. The diagram doesn’t know that you will be using it for something messing with the wave. The induction coil will measure the load current just fine.

[rubelstrudel]

The voltage of the output doesn’t change. It’s 240VAC all the time, so the meter doesn’t need to be after the controller to measure it. The power controller chops up the sine wave so that you get less than the full currrent going through the element, but you are still running it at 240VAC, you are just missing part of each cycle.

The wiring diagram is right in that you are putting it in parallel with the load. You should do that. Just do it before the controller which modifies the sine wave. The diagram doesn’t know that you will be using it for something messing with the wave. The induction coil will measure the load current just fine.

Well, that a chopped down sine is still the same voltage is not exactly correct. If it was the same voltage, ohms law would dictate that the current would not change over the same load resistance.

But other than that it is good to know that the amp measure is not dependant on the voltage of the input current. I'll do some tests when I have all my parts...

[jimmayhugh]

Well, that a chopped down sine is still the same voltage is not exactly correct.

Let's not forget that what we are looking at on the output of the SSR is no longer a continuous, purely sinusoidal waveform.

Whether you are using an SSR that begins the output at a zero crossing using an on/off signal,

ZeroCrossingSSR.png (14.46 KiB) Viewed 16618 times

or one that turns the SSR on/off based on resistance value,

NonZeroCrossingSSR.png (14.6 KiB) Viewed 16618 times

you now are dealing with a non-sinusoidal complex waveform, and most inexpensive meters display an RMS value based on a sinusoidal waveform.

To get the correct value of a complex waveform, you need a meter capable of "TRUE RMS".

There are many handheld multimeters that are TRUE RMS capable, and prices start at about $50 American. Panel meters are another animal altogether. I found one on Amazon that's out of my price range, although it also appears here for a lot less.

[rubelstrudel]

I'll have to dig out my scope now to have a look at the output of my thyristor controller and the ssr's I bought to build a new controller. Dunno if they're zero or nonzero crossing. Probably nonzero.

[sambedded]

All that SCR conrollers and potentiometer controlled SSR (SSVR) are using phase-angle control method.