Teardown of three STC-1000 style thermostats

How to use the classic STC-1000 clone thermostats, and a look at the circuitry inside them.
I think the original version of these units may be Elitech.
These modules are shockingly cheap for what is effectively an industrial control module. It's almost as if the software got out into the wild and everyone started cloning them in a common style of case.
As with all generic grey-import products you should only consider them for personal projects and prototypes. For professional or critical applications it's probably better to go with a higher profile unit for better construction standards and higher operational stability. That especially applies to where higher current loads are being switched. Although these claim to be able to switch compressors and heaters I would only recommend doing so via an external rugged high current relay. I'd also suggest a 12V DC system as the 12V relay coils are more rugged.
If you search on eBay for STC-1000 you'll find a lot of these at wildly different prices. Cost is not an indication of quality and what you get will be completely random - even when two are ordered from the same seller.
Here's a super compact guide to programming them.
The two main settings are temperature and differential (hysteresis), where the differential is the difference from the set temperature and is where the heating or cooling will kick in.
The compressor delay setting is to avoid rapid cycling of the compressor to prevent it stalling by starting under pressure.
The calibration function lets you tune the accuracy of the thermistor.
Press the up arrow briefly to check the main temperature setting.
Press the down arrow briefly to check the differential setting.
To change a setting press the "S" button for a few seconds to enter setting mode, and use the arrows to step up and down through functions F1 to F4.
To adjust the chosen setting press the "S" button briefly to display its current setting, and press and hold "S" while using the arrow keys to change the setting. If no button is pressed for a very ungenerous four seconds the unit will exit setting mode.
On some units the settings may not be stored unless the power button is pressed briefly while in setting mode.
F1 sets the required temperature. These units only operate in Celsius.
F2 sets the differential in degrees where the relays activate either side of the main setting.
F3 sets the compressor delay to between 0 and 10 minutes.
F4 lets you nudge the calibration of the thermistor to match a more accurate thermometer.
The temperature sensor is a very common 10K NTC thermistor. (10K ohms at 25C)
If the sensor is open or short circuit the unit displays EE.
Try to keep the sensor cable away from mains voltage wiring to avoid display instability.
To turn the unit on and off you can press and hold the power button, but this is NOT safe isolation/disconnection for working on wiring. It will self-reset to on with a power cycle.
To reset to factory default settings press and hold both arrow buttons simultaneously.
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#ElectronicsCreators

[@TotallyNormal-]

Ah ha! I was looking for a low voltage thermostat with an adjustable differential to use with my pellet stove! Using a standard thermostat with a pellet stove results in it cycling on and off constantly-the typical thermostats usually have a 1 degree differential. The stoves take about 20 min to shutdown completely, and about 5-10 min to power up and start producing heat. For me, an 8-10 degree (F) differential is perfect! (As well as time delays) thanks for the video!

[@johndododoe1411]

So 5°C differential (conversion factor is 5/9).

[@MichaelOfRohan]

Well it comes with a weaker thermocouple so if youre taking really high temps you might be out of luck. Not sure if theyll accept a k type.

[@MichaelOfRohan]

But, if youre in the us, Harbor Freignt sells a $23 multimeter that comes with its own k type thermocouple.

[@AtomicShrimp]

Must be something in the ether. Yesterday I dug out a single relay version of this style of device that has been lurking in my 'future projects' box for years, with the intention to make something with it, then that evening, I saw this video. Strange alignments!

[@LuminalSpoon]

Can we have a Big Clive and Atomic Shrimp crossover? Atomic Big Shrimp Clive

[@willallen7757]

@@LuminalSpoon Big Atomic Clive Shrimp .

[@joelaw728]

I vote a sous vide controller. I made a simple 'inline' setup with an old extension lead and an enclosure. Slow cooker with the probe in it for the bath. Best steak I've ever eaten, from the cheapest cuts possible (right up your street!!)

[@AtomicShrimp]

@@joelaw728 yeah. Sous vide, or temperature control for cheese making, or for a cheese maturing fridge. There are a lot of applications for fine temperature control that I could make use of

[@zac6x9]

@@AtomicShrimp I use mine to thermally control my 3d printer cupboard (keeps the filament dry)

[@piconano]

My experience has shown these relays to be incredibly dangerous. They arc weld easily. I bought one with exposed PCB that runs on 12V and only one relay, but after a few months it wouldn't turn on the heater. I found a relay like it on Digikey, and replaced it with a real Omron for about $10. 3 Years so far an no worries.

[@Margarinetaylorgrease]

Mine's been running non stop for 2 yrs, did I get lucky?

[@adrian_foden]

@@Margarinetaylorgrease Rather depends on the load you're switching.

[@Margarinetaylorgrease]

@@adrian_foden A fridge compressor.

[@johndododoe1411]

Unfortunately, when last visiting the Omron website to get specs and catalogs, all I could find was marketing noise about products for hospitals etc. Seems a bad trend among corporate website designers to hide their signature products under mountains of aspirations to enter new markets.

[@piconano]

@@Margarinetaylorgrease Without looking at a snapshot of a current probe, it's hard to say how huge the current to the motor at startup is. It's high enough that prevents most power inverters to shut down. If you have the experience, replace it with a known brand that matched that footprint. If you haven't done that before, don't start with this. Start with something less critical. Buy a better quality. Pay once, cry once.

[@noahsheehan7824]

I've been using STC-1000's for temperature control for my aquariums for years, with the oldest one being 6 years old. Simple, accurate, and cheap. The heat and cooling control is amazing. I have both heaters and chillers on my tanks and by using one controller, it eliminates the risk of having both the heaters and chiller on at the same time. Highly recommend them.

[@ALAPINO]

Out of curiosity, what chiller are you running?

[@noahsheehan7824]

@@ALAPINO EcoPlus 1.5hp, and 2 aqua euro 1/10th hp. (Separate Tanks/systems). All the chillers and heaters have their own thermostats also, so I utilize those as a redundant cut off. For example, System temp is set to 78°, the STC is also set there with a 1° deviation. So the main (STC)temp range is 77-79°, therefore I have the chiller set to 76° and the heaters set to 80° on their built in thermostat. If the STC was to fail closed, the heater/chiller will shut itself off once it reached its own set point. This helps prevent them from getting stuck on and freezing or cooking the tank.

[@ALAPINO]

@@noahsheehan7824 Cheers! Thanks for the information! That's exactly why I'm leaning towards something like an STC, cost effective redundancy. My old home gets very cold in the winter and very hot in the summer. Not ideal for the animals we keep. :P

[@noahsheehan7824]

@@ALAPINO Awesome! Glad I could help!

[@andystokes8702]

I'm using them for exactly the same function although I don't use the cooling function, just the heating side. I set the aquarium heater to a couple of degrees higher than optimum so that if this unit should fail in the 'on' position the thermostat within the heater will turn off before the water temperature gets too drastically high. I have had just about all types and makes of aquarium heaters and I have yet to find one that is reliable and keeps the same temperature, it seems that because most of them use a bimetal strip they will alter over time. The greatest advantage is that I can check the temperature of all my 6 tanks just by glancing at them from a distance, the majority of aquarium thermometers are a total pain to read.

[@gali01992]

I live in an RV (caravan) in Mesa, AZ where it can get to 120F (50C) in the summer. The back of the refrigerator is exposed to the outside and has a problem operating above 85F (30C) so I bought one of these to switch on a small fan at that temperature so that it blows on the refrigerator coils. This works pretty well up to an outside temperature of 105F (40C); after that, nothing will help and the temperature inside the refrigerator will go up to around 50F (10C). The refrigerator operates on 12v so I hooked it up to the 12v line coming into the back, and the device will work even when I'm on a trip and not connected to shore power. My project for this summer is to add a second fan that will blow cold air from inside the trailer into the area behind the refrigerator to increase the efficiency of the refrigerator on very hot days.

[@joegroom3195]

I've thought about adding a fan to my rv fridge as well. Good to know one of these will work. What fan did you use?

[@gali01992]

@@joegroom3195 I bought a 12032 brushless DC cooling blower fan (2 pin) from eBay. I bought it for $7.50 but current prices seem to be around $20.

[@SovTekBestTek]

I LOVE THE STC-1000! I have one I installed to control a deep freezer, and it has reliably served for at least 5 years now. Never an issue, perfect absolutely perfect little device.

[@Weissenschenkel]

Seems about right for controlling a fridge full of Lager beer during fermentation! Also love the pro tip regarding relay failure that can be mitigated with a bimetallic switch and a neon bulb + resistor as failure indicator placed across the switch. Neat! Thanks for sharing!

[@SaberTail]

These aren't the same units, but I learned not to trust the relays in these types of things after a PID controller running some simple resistive heating tape managed to fail after only a few months. The relay got stuck in some halfway-closed state and emitted a bunch of smoke. After that, I switched to having the relays in these switch a solid-state relay that would switch the real load. More expensive and less efficient due to the drop in the SSR, but never had problems after that.

[@tubastuff]

I use one of the Chinese PID controllers in a lab oven. (moderate temperatures

[@petergamache5368]

There's a substantial difference between an ordinary relay and a contactor: the latter is built to handle much more current and is arc flash resistant. In resistive heating or other high-current applications, a contactor is usually the safest choice. SSRs are also good, but beware that SSRs can sometimes fail and when they do, they usually fail closed - meaning the circuit stays live.

[@tubastuff]

@@petergamache5368 Hence, the need for a thermal fuse in heating applications. The actuating circuit can fail with contactor permanently activated. Belt and braces for safety is a good rule of thumb. In my lab application, the heater is only 75W.

[@marcussoininen2084]

I've used one to cool a fermenting beer, to 18°C in a 21°C room, it ran an aquarium pump that sat in a cooler filled with ice water, replaced ice as needed. It worked well for that at least, ran for about a week.

[@javaguru7141]

That's cool. How much ice did you end up needing for that? Was it a once-a-day 10 pound ice bag thing?

[@PaulLemars01]

I came across these PID controllers when I was upgrading/modding my Gaggia Classic Pro espresso machine. The normal bimetallic controller would control the boiler approximately within 10 degrees which if you're obsessed with espresso is no beuno. You can set the temp precisely on them and these little buggers will keep the boiler within a degree. I've also seen them being shoehorned into Rancillio Silvia machines.

[@LeePorte]

Shades of Coffee fan?

[@ohyou_6599]

I've had a 110v one in operation since 2016, It is used as a low temp cutoff for an array of server fans propped up in a window to cool off my room. it has switched up to 5 amps of 12v for years, but usually it's ran on a lower voltage unless its quite hot. they are great units for the price. at just $15 I've ended up with more of them now to just use as thermometers for various things. the relays are an added bonus at that point

[@CountDrunkula]

I've been using these with my fermentation fridge for years with an incandescent light bulb, and for controlling a freezer as a keg fridge. I also use Inkbird 308s but the non. WiFi version has occasional temperature transients that cause the fridge to kick in for a brief time occasionally (it's a known bug they know about) and its cali bration can shift. I find cheap stcs more reliable than 308s.

[@phils4634]

I've been using one of these for ten years! We use it to drive a heating pad, so our parrots are nice and comfy during our chilly winter nights, and it's been absolutely reliable. Mind you the load switched is only 25W (so 100mA) resistive. Easy to set up, and easy to get parts for (important for when "they" chew through the NTC probe cable!)

[@packratswhatif.3990]

I have a couple of these units here in Canada to control a freezer and fridge. So far they work great and yes I used an external relay for control. Love to fact that they readout actual temperature of your appliance. 👍

[@kevinhardisty6465]

I remember paying an OEM $700 for one of those for a hospital refrigerator. The management insisted we do it

[@petergamache5368]

And what would the cost of a full refrigerator's worth of medications be, if it failed? Probably a lot more than $700...

[@javaguru7141]

@@petergamache5368 Which more begs the question of why they were using an STC-1000 for such a critical application to begin with :\

[@Thingstest-rl8xu]

For those that miss an important point: Switch/Relay ratings printed on them is _near always_ Max Amps at VAC unless actually says VDC and all for purely Resistive Loads. Look up data sheets and you find the rating for Inductive at best is 1/3 to 1/2 of Amps for given Max Volts. Even parts made by Omron and other well known brands have same markings on them and will burn with Inductive Loads. Motors, fluorescent and other lights with a ballast, transformer and more will burn down any switch point fast because of this. But Some Datasheets don't bother listing this info and many people burn out the contacts and worse...

[@brianleeper5737]

So-called "definite purpose contactors" are rated in amps for an inductive load. Therefore a 40-amp definite purpose contactor is rated for a 40 amp inductive load. They're primarily used in HVAC applications to switch motors and compressors, and may only be available in USA/Canada.

[@johndododoe1411]

Yes, when I tried to design my own relay boards I found this to be buried deep, and often with no useful numbers for individual products. Also the published information on prolonging contact life with snubber networks falls into the useless category of "measure your very specific finished product and redesign circuit for that specific situation", which is highly impractical when trying to make something intended for 3rd party use with unknown loads. As a workaround (never built and tested), I considered using a MOV to eat the back EMF from inductive loads, thus preventing excessive contact wear.

[@pauls5745]

now i know why regardless if we over spec our relays, we always end up replacing them anyway just farther down the line

[@Thingstest-rl8xu]

@@brianleeper5737 The Contactors goes by different names but they do use versions world wide. These are not cheap or available to general public in normal retail. In the U.S. you are often looking at Graybar and other industrial suppliers to buy them and meet Electric Codes.

[@Thingstest-rl8xu]

I looked but Can't find exact JQC-3FF above. Others start same and FL-3FF-S-H the datasheets have No mention of Inductive loads. Contrast to Songle SRD-05VDC-SL-C (Used by Elegoo and many other Arduino/Pi kit makers) Datasheet rates Type C contacts Resistive Load 7A 28VDC, 10A 125VAC, 7A 240VAC Inductive Load 3A 28VDC, 3A 120VAC If part number end with A means Type A contacts rated for Resistive Load 10A 28VDC, 10A 240VAC Inductive Load 5A 28VDC, 5A 120VAC Omron sheets are similar with reduce I-loads for most relays. Some Relays for Cars are made to handle 10 to 20 Amps at 20VDC because controls Fuel Pumps, AC Clutches, and more but they often wear out faster doing that vs Turning On Halogen Headlights pulling More amps then the motors/coils. Same problem at home with standard wall switches burning up every few years at best controlling garbage disposers, fluorescent lights, etc.

[@connclissmann6514]

I used 3 of these (mains voltage type) to control three (Beko) domestic full-sized chest freezers, in order to maintain them in the range -25 to -18 degrees C. This was required to maintain chemical thermal blocks within a known temperature range prior to use in pharma shipping of cold chain products. They (and the freezers plugged into them) worked flawlessly over 3 years, at which time we left that business. Great to see the innards and learn of their circuitry, as always. Like you suggested, I always kept two units as spares (given the low cost) but they were never needed. I would happily use again, should the need arise.

[@adrian_foden]

I think a return visit is required Clive, the relays and their real-life current switching capacity and the loads they're capable of dealing with are where the rubber hits the road. A brief run through the comments here says there is a story to be told. Jumping into some of the datasheets for them is.... interesting!

[@transmitterguy478]

Clive, I have the Inkbird ITC-1000F in my house, its very similar to yours but its display will support Centigrade and Ferinheight. Here in the USA that helps. It functions a little differently than the SCT-1000 but is the same case and connections. I have hot air oil heat so I have mounted the thermocouple into my dryer vent that I change to vent into the basement through filters. When the dryer vent reaches 75 deg F it turns on the fan in my furnace and dissipates the heat throughout the house along with the humidity in which is greatly needed in the winter. Works great!

[@AvgDan]

I used one of these to convert my dad's old analog electric smoker for his birthday. It made the smoker maintain a much more precise temperature. I got one that had a 30A relay built in.

[@iconoclad]

I have two similar 240v units mounted in a box by my bed. I have one temp sensor in the bed at foot level under the electric blanket. I set this at 30c. The other unit is wired in series, measuring the room temp, set at 24c. The electric blanket is set on #3 ( full heat). All this is powered by a clock timer to run between 10:30 pm and 7:30 am April to September. I was so sick of waking up shivering at 3am or covered in sweat if it was a warm night. So now I have the Goldilocks setting and it is just great. Its has been running for nearly ten years. Plugged in last week for the on coming winter.

[@thewhizard]

Agnone know where i can download the BigClive theme pack for windows? Every time I open a new program i want it to say "one moment please"

[@jameshunt2141]

been running these for my household fridge and freezer for ages. brilliant for the price

[@DarnWhippets]

been using these mains cheapies for heating/cooling various greenhouse and seedling tents as well as a ferminator for fermenting chilli mash. They're cheap and chearful, not had one go bang yet, and they're powering oil filled radiators, bench heaters and fridges. Fantastic little beasts.

[@PorkySubstrate]

Great to see you finally look at this. These are quite commonly used for fermentation temperature control. They always crop up as a cheaper alternative to Inkbirds and I've even seen them in professional breweries. Would be interesting to see the guts of the Inkbird in comparison.

[@christ2290]

I use one of these as a "freeze guard" on our central AC unit. I threw it in while I was waiting on some R22 a few years back but after I fixed the issue and recharged the system, I ended up leaving it on just as a failsafe. If my suction line gets below 5C, it cuts off the condenser and just lets the inside fan run by itself. Just set the cooling temp to 6C and a 1C swing. It's wired to always be on and only the condenser control line is switched thru it. I set the compressor delay to 10 minutes so if it *does* start to freeze, it'll kill the compressor for 10 minutes to let the evaporator thaw. I know 5C isn't freezing but if the suction is that low, icing has already started on the evaporator on the first few loops after the expansion point and once the first few turns start to freeze, the rest will ice pretty quick. Great video as always Clive!

[@SheriffJackCarter]

I have one of these units. I put my Ender3 in a 12-U enclosed/vented networking cabinet. The cabinet came with a pair of 120mm mains voltage fans. I routed the temperature probe wire through the cable chain onto the Z-Axis Rail so the probe is about 20mm above the print nozzle or the piece being printed. I have the temperature set to 37.7˚C (100˚F) with a 3˚C Differential. Compressor setting disabled and the fans connected to the cooling side. Nothing is connected to the heating side. This keeps the ambient temperature hot around the print but kicks the fans on if the temperature rises too much. I found it helps to prevent the print from warping and coming off the print surface during printing.

[@gilbertsprojects2954]

Great video as always, interesting as we have these (or very similar dual temp version) in the vans at work (supermarket grocery delivery) for the chiller/freezer compartments.

[@cidercreekranch]

I've used a similar device for year to control the temperature in a mini-fridge that was being used as a cheese cave. Though the one I was using was mains powered (120v) and had more buttons and configuration options. I recall that I could set an audible alarm for when the temperature went well below or above the set points.

[@ohmbug10]

I use an Inkbird in a gutted out mini fridge for starting plant seeds. It runs a 40watt incandescent for heat and a couple of 80mm fans for cooling. A Defiant timer switch controls CFL lights. Hole sawed a bunch of holes for fresh air.

[@BradsGuitarGarage]

I had 2 of the real Elitech versions of these in my hombrew set-up 10+ years ago, installed in a jiffy box with IEC connectors for input, heating (during fermentation in winter) and cooling (during fermentation in summer and to turn a freezer into beer keg fridge). Passed it onto my mate as I have no time for homebrewing anymore, but it's still going strong!

[@bigclivedotcom]

Elitech video recorded and coming soon.

[@deathcogunit106]

I've been using a nearly identical one (humidity instead of temperature) to control a food dehydrator for drying 3d printer filament for several months, 120v version. No complaints so far.

[@HughsScamProducts]

I have 3 of these and the one that does temp and humidity. In the US they have optional f or c display for temp. I use on as a back up for my dogs heated bed and have used them for temp controllers. They work great but have to be done right so connections don't come loose in certain applications, especially where vibration happens. Ferrules are a must and then strain relief

[@sublimationman]

Iv'e been using a 110v version to turn a chest freezer to epoxy storage (keeps it at below 50f) for many years. They work great and my first one lasted about 5 years and the current one is on year 7 right now. I sell the epoxy and it has to be stored somewhat cool

[@TheGhungFu]

Love these things. I used one to make a sous vide machine out of our slow cooker. Must be a manual (not electronic) slow cooker.

[@joelaw728]

Same here. Absolutely amazing results. Made mine using a basic enclosure box and an old extension lead. That way I can stick the probe and meat in any slow cooker; future proof and didn't need to modify my slow cooker :)

[@TheGhungFu]

@@joelaw728 Great minds think alike? I can use my little friend to control the temperature of many things. I also am building another to use with a small freezer for a cheese cave.

[@brainfarth]

I used one of those to control a mini-fridge that was left out in the sun and blew up the thermal control. I duct taped it to the top of the fridge and it worked for years. Great deal for around $10.

[@uSlackr]

I've been fermenting with two of these for 5-7 years. Using 120V power source and running a small refrigerators directly on the load side.

[@instography]

I also have a couple of 240V / 40A versions that I use for brewery water heaters. They've worked happily for a few years now after a normal mains voltage one went smokily overloaded. I use normal mains ones to run a big fridge, small fermentation heaters, greenhouse propagators. One thing I would recommend is putting them in metal cases. They're cheap and disposable but they also fail.

[@raygale4198]

I have a few of these running, both mains and DC powered. One AC unit has been running for near 10 years controlling a cooling fan on my grid tie inverter system (non kosher). Another DC unit has been controlling via a power relay a cooling fan on my Land Rover diesel, Lucas electrics have not managed to destroy it in 12 months so they must be tough.

[@StubbyPhillips]

Thank you dear Mr. Big Clive sir. Have a swell day!

[@mlmmt]

I love these things, I have a slightly different one connected to a box fan I shove in my window to cool my room off during the evening!

[@MrJohnnaz]

I have 6 of these running dye heaters, they work well. I did not use the stock relays though, they were de-soldered and wires were ran to the existing terminal block and wired to external solid state relays. I also updated the tags showing that they were modified.

[@roy2689]

In our laboratory, (no longer in existence, company restructure etc) we had large water heating tanks (proprietry) to test ground samples, they had exactly the same control panels as these, but the internal relays kept sticking and the water would boil away (the tanks were left running 24-7 over several days to complete a test), it was obvious that the internal relays were woefully inadequate to switch the heating element loads on and off, so I wired external 30 amp relays (RS components), in a similar fashion to the unit you showed towards the end of the video (21.13), and they worked perfectly after that...

[@shanerorko8076]

I used one of these on a friends converted fridge for home brewing. It just had a heat pad in the fridge and we had a 60l brew drum which we just fit into the fridge so he could do 45l batches.

[@redeye619]

Theses are fantastic units for the price, I have used them in a many of projects from aquariums to walk in chillers/freezers to saunas, even put one in place for temporary use for the radiator fan on the van, always with external relays as never trusted the tiny little things in there, buy they have proven to otherwise be very reliable

[@Petertronic]

As a few others have mentioned, I'd love to see you investigate an Inkbird one. I have two Inkbirds which I used over the winter to precisely heat rooms - very accurate, useful and energy saving indeed. I also have the humidity variant which is also proving accurate and reliable - the huimidistats built into dehumidifiers are often wildly inaccurate. I swapped out the generic relays with Omron ones - the STC-1000 relays look like Omron G5LE pattern clones.

[@v8snail]

I bought a version designed for thermoelectric devices which swapped the polarity of the output for heating or cooling. It's used for brewing beer so seasonally heats or cools. It has been switching 6A @ 12V for about 8 years with no issues. 12 Aussie dollars delivered back then.

[@RevvyTone]

Ha, the STC-1000 for a number of years has been the favorite heating/cooling modules for homebrewers for beer temp control during fermentation and to control the temps on our keezer beer taps. Eventually a company noticed we were ordering these cheap buggers and repackaged them as the "Ink Bird" controller for brewers. Also before home Sous-Vide immersion circulators were under $1000 I cooked using them with a coffee urn and an aquarium pump to move the water.

[@acmefixer1]

We saw these were made for mounting in the front panel of a piece of equipment. Perhaps the next one you get will be a surface mounted box, like that found in the home environment? Thanks for the great video.

[@elco_os9355]

I have once repaired a very similiar thermostat that controlled a fridge. Due to moisture build up, a leakage current was flowing over the pcb from live to neutral. This resulted in a trace of carbon which was conducting enough to short the live to neutral with a loud bang. I had to cut a slot into the PCB in order to remove the carbon trace and to gain a better separation between live and neutral.

[@soniclab-cnc]

I used that controller for my laser chiller I built from an air conditioner. Nice it has a compressor rest function. I set a 3 minute delay between cycles as many compressors require. It has been working very well and keeps my 130 watt Co2 laser at the perfect temp. I used a low voltage and and external high quality relay for switching ac voltage.

[@goosenotmaverick1156]

Theres so many cool uses listed in the comments, so far yours has got to be the coolest. I'm not smart enough to build them but I've always found lasers fascinating

[@soniclab-cnc]

@@goosenotmaverick1156 lol yeah, i built the laser cutter too. Its a beast!

[@electrowizard2000]

What's your set temperature? Any data on tube life vs temperature? Thanks!

[@soniclab-cnc]

@@electrowizard2000 each manufacture will have optimal temp ratings.... usually less than 20c. I run my chiller at 12c and the tube stays at 15c at 90%. I set the max current to 90% to extend tube life. 10,000 hours rating on this tube if run within spec.

[@chrisprobert6]

Hi mate. I used to work for a commercial cleaning equipment contractor. They supply a machine called a decarboniser. Using one of those to heat either 10,35,50 gallon water tanks using domestic elements used for central heating. It was a smaller part of their business but u used to replace approximately 5 of those controllers every week !!!

[@SaucySpecial]

This does look like a generic version of an inkbird temperature controller, which seems more robust from my experience while still being relatively inexpensive. I'd be interested in your take on an inkbird.

[@Chemist1076]

I have used ink birds twice with external SSR no problems.. nice to have cheap tech for projects

[@charleslambert3368]

I've used an inkbird hooked up to a slow cooker to make yoghurt, with moderate levels of success.

[@samholdsworth420]

@@charleslambert3368 moderate levels of success and yogurt = 😵‍💫🤢🤮😵

[@dandesloover5541]

​ @Charles Lambert I've used one of these cheapies with a slow cooker for Sou Vide and also heating element for brewing and also with a freezer for lagering with great levels of success. They're not that bad.

[@DrakkarCalethiel]

They are amazing for the price. Used them for my resin heating chamber and chiller.

[@ConstantlyDamaged]

"What's that?" "Oh, that's the *_call engineer now_* light." "Why is it covered with tape like that?" "It keeps lighting up and I can't work out why."

[@bigclivedotcom]

Or "Oh it's just gone out again so we don't need to call them."

[@nat7278]

I've got one of those I used in a camper build. Seemed to work well.

[@JamesWilson-gw2ij]

A very great piece of kit.

[@UglyBigZombie]

I have a mains version (120V) controlling a small bar fridge. It's been running fine for a good many years. They're great for the price.

[@justme5384]

My freezer control panel broke last weekend, luckily I had a few STC-1000 on the shelf. The freezer only had the probe and three wires, neutral and line in and line out to the compressor

[@jstro-hobbytech]

Thanks big guy I have a similar one for monitoring a 200watt heater for a 3d printer enclosure. I have yet to test it because I have a kitchen to tear apart and build anew haha

[@electronic7979]

Nice review video 👏👏

[@amorphuc]

Thanks Big Clive. Interesting stuff indeed!

[@olegvelichko1659]

Been waiting on this! Have a few beating around in my stash. Wonder if there’s anything worth scavenging from them! Looking forward to this!!!

[@Sylvan_dB]

I've seen some of those with dual sensor sold as a differential or relative thermostat. This is where it compares the temperature of the two sensors and turns on if the difference is high enough. Usually combined with absolute, so for example T1 at 30C minimum and T2 5C minimum difference. Often used for solar thermal collectors, to control the pump used to transfer heat into storage.

[@devttyUSB0]

Sometimes, just sometimes, you get a variety of products labeled the same from the same seller. It's hit and miss, mostly. Cool video, again!

[@HoverdogBrewery]

As others have said, a lot of home brewers use these for fermentation control. I have one to control the heating & cooling of an old fridge in which I put my fermenting beer. Check out the Rex-C100 devices cos they were similar and popular devices for brewing control but are 3 term PIDs instead of what is basically an on/off switch. I use a similar device, the Elitech EK-3010 as a replacement for the controller on my fridge/freezer as the original capillary type device died.

[@jaaxxone]

With more than a grain of salt... I have a unit like this controlling a 1500 watt (100v) heater coil on a smoker that has been perfect for over 8 years so far. You never know what you might get!

[@cetyl2626]

I've used one of these to control for fermenting beer and also for my beer fridge (a chest freezer) for 10 years.

[@richardbriansmith8562]

That was interesting and AWESOME big clive

[@minipepy1]

I use one of these controllers to run the freeze and harvest cycles on my ice machine after the thermostat failed, switches a contactor, and has been perfect for years, creates much more consistent ice than the thermostat ever did

[@loonyloony6550]

Nice! I have been using one for years.

[@jp040759]

Seems like a nice unit. I wish I had an application for one to get one. I have a W1209 and haven't found a use for it for 5 years. Bought it just to play with. Hopefully it finds a home in a project. Thought about using it for monitoring batteries being charged for safety cut off if the batteries get toooo warm. Still thinking about it. LOL.

[@charlesflecknell8550]

I've just bought one on ebay, Elitech, it's a newer version now (new shape😆) I've been using the old shape 240v ac version in my bike shed for years. When compared to eliwell or carel etc they are a bargain 👍👍

[@mrfixit100]

Fitted a single relay version into a enclosure switching a 20amp contactor and single switched socket outlet as a portable heavy duty heat controller works a treat.

[@anttiharinen6301]

Have similar gadget for humidity, very similar component layout. Date in board says 2014. And yes, it has a buzzer right there. Loud one!

[@benbaselet2026]

Those buzzers always need a piece of tape or blue-tack on them to be sensible. Good for loud environments of course.

[@jasonkuehl639]

I use STC-3028 (temperature and humidity) line voltage controllers for a 250 watt heater and a humidifier in my small greenhouses, and the only thing that seems to be common between all them is the board and the case they are in. I actually like them because they are cheap, if they go bang, I can toss it in my spare parts bucket, and throw another one in service. I've noticed some use a 3 wire temp/humidity sensor, and some use a 4 wire sensor. They seem to work well enough, and since I'm in the greenhouses daily, it's pretty easy to tell quickly if they've gone up in smoke. Some day I might try more expensive controllers, but for now, they work well enough.

[@ALAPINO]

I've been meaning to build a thermostat/hygrostat unit for my reptiles and other animals but haven't had the resources and time to start. For now I've been using cheap mains heating pad thermostats (iPower BNQ-T7B(H)) and a lot of manual monitoring for humidity and just verifying temperatures with an IR gun. Thank you, as always, Clive for your insights. I think I might go with a similar setup using one of these with redundancy. (A unit designed and sold for use with reptiles and animals with all the features I desire are $300, another reason I want to build my own)

[@Mad4400]

I built a number of these for use with reptiles, controlling heatcords, mats and ceramic emitters. Also used one for my incubator (small wine fridge) and achieved very constant hatch rates. I thoroughly recommend them.

[@ALAPINO]

@@Mad4400 That is awesome. I really appreciate knowing that someone's use case is similar to mine. Did you put them into enclosures or just use them as is? Thanks a bunch!

[@Niky272]

I'm also using one of these for my reptile incubator, which is basically just a big chunk of styrofoam with a lid that has a hole cut into it for a window. The hole is then covered with some clear acrylic. It works pretty well and the hatch rates are solid.

[@TheMrVengeance]

Been using one of these for years on 240V to run my homebrewing fridge. Keeps the ferment going at 17-18ish Celsius. Haven't had any issues.

[@geoffgeoff143]

Aimed at home brew market. Ive used a 240 volt one for years. Runnkng fridhe and heater belt. Safety issues include no segregation at terminals, single pole relays.

[@mysock351C]

I wonder if any of the 12V or 24V ones get accidentally shipped as "mains AC" units. The fact that they are pretty much the same externally is a bit creepy. Plug it in and end up with a nice smoke and fireworks show, with a temperature reading of "flames."

[@Nigeria_slime]

I'm very glad it keeps the heating cooling on until it reaches the set temperature I need it for thermo fans and I don't want them going on off on off

[@LeePorte]

Got one on the tortoise hibernation fridge. Had it on there for a good few years.

[@jhill4874]

I attached an air conditioner relay to the internal relays. Works great for higher power consumption. Mine is switchable between Celsius and Fahrenheit.

[@DeathbyKillerBong]

very nice i have one to control temp in here in summer, when it goes over 23c it starts a fan, 230v version, fan is 135w, going in 3 years now.

[@RPrice_OG]

I used one of these by Inkbird to convert a chest freezer to a kegerator and another to convert an analog croc pot to a pretty passable sous vide cooker. Been thinking of using them in an automated brewing setup too. The kegerator has been running continuously for many years now.

[@campkohler9131]

After reading up on sous vide, one has to balance the desire for food improvement over the chance of getting poisoned. Yikes!

[@hadibq]

Great video as always👍 TY!

[@johndododoe1411]

Another main use for dual temperature sensors is to measure the outside temperature to optimized the regulation regime for a central heating boiler or pump. If it's cold outside, the building will need a bigger supply of heat to the local regulators in rooms.

[@themadhippy6911]

I think ive the granddad of these clones, an elitech stc1000 from 20/6/2009 according to the pcb.Looks the same on the outside inside its a different beast,proper old skool linear psu, all through hole components on the main board and decent clearance between the sensor tracks and supply,also clearance and slots around the relay tracks.And yep its even got a warning buzzer

[@bigclivedotcom]

That video has been made and is coming soon

[@gordoncomstock2459]

I've got an STC controller on a ceramic kiln. I believe it stands for Stoke Temperature Controllers, Stoke being the centre of the Potteries in the UK. My controller uses an AI chip that contains a neural network. The values in the neural network adjust themselves by monitoring the temperature and rate of change to achieve the desired heating and cooling ramps which is important in ceramics

[@pmpwiz]

Happy to see this video. I've got an Inkbird ITC 2000 which is very similar but is 110v, has a big brown transformer inside, and what looks like a buzzer. Tried using it as a room thermometer but consistently read way too high. Now have no clue as to what to use it for.

[@punkdigerati]

It should be able to be calibrated if you have a trustworthy reference.

[@sparkyprojects]

Sometimes you have a changeover on one relay so that you can't have heating and cooloing on at the same time I would add ceramic capacitors across the contacts to reduce arcing. or use the modules to control solid state relays

[@davidlee4530]

for the 'industrial grade' controllers, usually uses output for solid state relays. this way its possible to control the firing of heater at high rate for PID control and at zero crossing. prolonging life of the 'contactor' and the heater itself.

[@matthewellisor5835]

Oh, it props-up my soul that I'm not the only one leaving Neons as indications to call "that guy who comes to fix things."

[@bradhoward9701]

I have had one of these apart with an atmel chip mounted on the back of the display. I didn't investigate any further, but it suggested the possibility that the chip could be reprogrammed with some standard arduino kit. I wonder whether there would be programming space for a pid upgrade?

[@Johnjoe321]

Aah the go to device for homebrewers there was a 30a one for sale at one point, handy for 3kw elements in kettles.

[@bigclivedotcom]

I have a 30A unit here in the queue.

[@theSam91]

Good stuff, just have me an idea to heat a greenhouse in winter

[@FuquarProductions]

I use one of these on my shuttle bus to control the rear heat/cooling. It is a nice addition without it the heat in the back can be unbearable.

[@luminousfractal420]

Nice, I've had one sitting there waiting to become an egg incubator control, but didn't exactly trust the mains connections on it...will be watching this one closely 👍 much better than panty cleaners lol

[@jrevillug]

The dual thermistor contacts could be for the STC 3008 dual temperature controller? I just picked one up to try as a cooling fan controller for my project car. It'll have beefy external relays for the actual load, naturally. Using the 12V version with a proper 12V supply also gets around the poor isolation of the thermistor port.

[@rollatorwieltje]

I'm using a mains powered one to control an old under-counter fridge repurposed as "climate controlled" cabinet in my shed to store paint etc. Put a small heater element in the fridge as well to heat it in winter. So far it has been running for about a year. Just to be safe I put it in one of those extruded aluminium cases, outside the fridge. Would be fun to actually try to switch 10A with those relays, I bet it will grenade within a few cycles.

[@ZacabebOTG]

14:27 Gotta love the fake ST Microelectronics logo on the voltage regulator being so Barbapapa that it technically isn't an ST Microelectronics logo anymore.