The COP menu item is likely used to copy the current settings over the "default" factory settings. Generally to do this, you get to the COP entry and then within 3 seconds hit the "OK" button (which in your case is likely the Set button). It will then say "YES" and stores the values to the internal flash as the default values. That's how a similar model I have works, in any case.
@@andrewpatterson5349 Why would they code such a feature when the user can just change to an NC-relay? It seemed like there was only two COP-options, 12 and 15. Do you think they are a choice between IEC utilization categories? (AC-12 is control of resistive loads and solid state loads, and AC-15 is control of AC electromagnetic loads)
@@johndododoe1411 The ones I found do have a different transformer with 110VAC input using this wording on the listing: SF-102 Thermostat Controller Electronic Temperature Thermostat Freezer US NEW
An interesting controller, I like the external transformer and relay connection. Makes it so easy to interface with different control devices - relays, SSRs, contactors.
The internal transistor and power supply are unlikely to be adequate to drive a contactor. You could, of course, use a small "pilot" relay for the contactor coil. BEWARE! Some contactors have two coils - a low resistance coil that pulls the armature home and a high resistance coil that keeps the armature pulled. A microswitch that is opened when the armature is pulled opens the circuit to the high-current coil. This is a good arrangement for saving power and keeping the contactor from running hot due to coil current, but it is a rude surprise if you aren't prepared for it.
7:31 minimum restart time is very useful for heat pumps (which also contain a compressor) - for example Daikin recommends a minimum of 6 minutes between runs.
Also makes it more versatile too. Need it to drive a bigger motor? Get a bigger relay. Want to have a whole bank of these? Get a bigger transformer and run them all off it.
@@ConstantlyDamagedCircuit also works from a DC supply that happens to power a larger control system . It looks like it can even run from an industrial 24V DC system .
Some times there are setting for different probe types in the hidden menu. so you can change between TC and RTD measurement etc also different TC types.
In over 30 years I can't remember seeing one of those 12v transformers fail. Usual failure on those style controllers in refrigeration applications is the compressor relay sticking on.
the delay time is also good for recovery from power failures. Setting 1 minute will prevent it chattering on a messy power up. I just had a relay burn out from that very reason.
Just to emphasize the point that other people have made, the external transformer and relay aren't just good for maintenance but also for systems where you already have the appropriate power and something else to switch. Just for example you can use this as a temperature monitor hooking the power side into a computer interface and the relay side into an ADC or digital readback. In that case you might not want a relay involved at all.
We have similar devices behind the bottom cover of our chilled display fridges at work. I was watching the engineers re-gas a faulty unit once and I believe the defrost side is an element very similar to a grill in an oven, sat in the bottom of a drip tray where the hot side of the pipework is coiled up and sits in with it, presumably to boil off water from condensation as our fridges do not have a plumbed drain on them. In the freezers it will run around the cold side to melt off any build up of ice, but the freezers are connected to a local drain due to the amount of water that will be generated. I also believe the "data" line on the unit is connected to a wall mounted device called a 'Plant Watch Pro' in our shop which monitors the state of the fridges and displays their current temperature and can be programmed to call an engineer if a fault condition occurs or the fridge runs too warm for too long, setting off an internal alarm on the panel which has to be acknowledged by a user who then decides if an engineer is required. Fascinating stuff and I guess most people wouldn't know supermarkets go to great lengths to make sure food is kept in safe conditions (albeit a law requirement anyway lol) Thank you :D Id love to get one of those temperature things to muck about with. Could COP be a short hand of Compressor Overload Protection? meaning after a set time a user thinks is too long for a compressor to run, regardless of temperature set it will shut of power to the compressor for overheat protection? Not sure. x
Completely depends on the system. There is no one defrost system type even on similar equipment, to say nothing of the fact that medium temp refrigeration circuits generally don't even have defrost heaters, they just use air defrost and keep the fan spinning while cycling the compressor off
COP can't mean compressor overload protection the way you explained it, because the compressor may run for much more than an hour after the deicing is done, or after the fridge has been started warm. The overload protection may only be used following an off cycle, setting the minimum wait time until the next on cycle, in minutes.
Most STC-1000 clones have heat and cool outputs and operate both cycles. This is handy for things like fermentation chambers (for brewing or baking) where you may want to target a temperature that is higher or lower. Add a couple external spdt relays and you can control a thermoelectric device to behave as both heater and cooler.
Yeah, but there's only one output on this unit, so your first relay is either on or off. The STC-1000 has two outputs so you can set cold and hot points, but the output is via two separate relays.
*COP* _might_ mean *Coefficient of Performance* (of a heat pump), which could be calculated approximately from three temperature inputs, in the model equipped with all three.
nice to see ferrules on the end of multicore cable, on friday i went to change a cracked junction box, ferruled the twisted light cable, only to find then they would not go into the terminals... brilliantly compatibility of products, thanks fixscrew.....
Cool, I have worked with most temperature controllers, like you mentioned some only do a good job at heating or cooling but some can have multiple stages I have worked with some that had 4 stages that can be used for heating or cooling so you could use multiple heating systems or cooling and they also have a hysteresis function so it learns how long it takes to heat or cool an area when you want the best temperature control...
The Coefficient of Performance (COP) of any heat pump will vary as either the inlet temperature or the heat pumps outlet temperature varies. As the inlet temperature increases from the ground, the COP will also increase. That multiple is known as the Coefficient of Performance or COP. As the temperature warms up outside the COP increases. Compared to electric resistance heat, even at -5 F, a heat pump puts out 2x more heat than a resistance heater using the same amount of energy input, or it is 2X as efficient.
It's interesting that they left all three output channels populated despite only using one. The pads on the right with 0 ohm resistors look like configuration jumpers. Maybe you could enable the additional functionality and outputs just by bridging the correct combination of pads?
Clive, I just got sent this link and I thought I’d share it with you. It seems like a great source for video ideas, in case you’re running low. I know you’ve already seen some, but others might be new to you. I love all of your content. Thanks for all you do! 😊
Yes, but the hysteresis won't work as expected. When temperature became greater than Setpoint It would cool down to (Setpoint - Hysteresis) degrees. Of course you could unintuitively set your Setpoint to (Desired Temp + Hysteresis) degrees and it would behave more like a proper cooling controller.
I figured those circuit board connecrors out the hard way. Had un and redone some connections onto a dimmer a few times to many and it snapped off. I ended up soldering the wire onto the remaining pin which was also my very first soldering attempt. It seems to have worked as it still works fine and hasnt blown up.
Process Tech here. If this is indeed for a heat pump, COP may mean Coefficient of Performance. For my (company's) money, I use Love and Jumo temperature controllers when I need standalone PID temperature control. They're well documented and that alone is worth the premium.
Great circuit. I think that I would have been tempted to place the NTC & 10k resistor filtering on the other side of the 22k resistor, but this is not a biggie!
*Summary* - 0:29 The temperature controller being discussed is superior to generic eBay models. - 0:56 It has better construction and uses traditional power components and an external high-current relay for easy replacement. - 0:59 The controller includes a potted 2VA transformer and good filtering on the thermistor input. - 2:16 It is suitable for resistive heating loads and can control up to three external relays. - 2:51 The PCB is standard with provisions for two thermistors, potentially a third, a fourth button, and a sounder. - 0:39 The unit was purchased at a lower price because it was sold as a refrigeration controller instead of heating. - 4:13 The display shows the measured temperature, and pressing a button allows the user to adjust the set temperature. - 5:00 Programming features include setting the user-adjustable temperature range, hysteresis, delay start, thermistor calibration, and unit measurement (Celsius or Fahrenheit). - 6:23 Hysteresis and delay start prevent rapid cycling of loads and reduce stress on equipment. - 8:30 The video's presenter is curious about the real-world reliability of these controllers. - 9:12 The transcript details the presenter's examination of the controller's design, functionality, and settings. - 9:37 The controller is noted for its industrial application and serviceable components. - 13:39 *Reverse engineering begins* - Designed as a universal unit for refrigeration equipment - Has three outputs to switch three relays: compressor, defrost heater, and fan - Suitable for cold rooms or refrigerated cases in supermarkets - Controller cycles between cooling, defrosting (heater on, compressor and fan off), and then back to cooling - Includes a beeper for alarm situations - AC input converted to a rectified and smoothed DC voltage (14-17 volts) - Voltage regulation and filtering capacitors provide stable supply rails - Microcontroller drives the display and buttons via multiplexing - Supports two thermistor inputs with an option for a third one - Unregulated 12V output, ground, and data line for remote display/button interface - Features a programming port - The circuit includes a transformer, a rectifying bridge, voltage regulator, and filtering capacitors - Thermistor inputs are heavily filtered to ensure stable readings - Microcontroller drives the multiplexed display and processes button inputs - There are four transistor outputs: three for relay control and one for the sounder - The design includes snubber diodes to protect against voltage spikes from relay switching - The board is versatile and designed for reliability and serviceability - Components include a durable transformer, high-quality relays, and a robust power supply - The unit is designed to be long-lasting with low-frequency power components - Model SF-101 SH general purpose temperature controller, versatile and reliable
Practically every consumer product sold in the U.S. in the last 40 plus years has been manufactured in an Asian factory which means anyone smart enough to figure out how to set up one of those controllers is very familiar with the centigrade temperature scale as well as the metric system.
06:20 - Hysteresis Very interesting tear-down. Thank you Clive. ----- I am struggling to understand the difference between controller hysteresis and controller dead band. My tentative, incomplete, and quite likely incorrect understanding is that hysteresis and dead band exist in completely different dimensions, i.e., hysteresis is always-and-only a function of time whereas dead band is always-and-only a function of the process parameter that is being controlled (in this case, temperature). If that is true, then for an ON/OFF (non-modulating) heater controller: 1. hysteresis is the minimum amount of time that shall elapse between calls for heat; and, 2. dead band is the range of actual process temperatures in which the controller will not change state between ON and OFF. Helpful comments by trained and qualified instrumentation techs are invited.
Hysterises is the temperature difference between compressor/heater on and off. Dead band is the difference between between being in cooling or heating mode. Eg. Set at 5C with Hys of 1 and dead band of 2 will give... 6C compressor on 5C compressor off 4C you are in the dead band - nothing happens. 3C heater off 2C heater on
I thing you should probably use an external with all these small temperature controllers. I removed the internal relay in mine and jumpered the contacts accordingly to use it with a solid stater relay without risking the internal relay failing. I have heard that it is not uncommon for recovered relays to be used in the cheap knock off pid controllers among other things.
In HVAC COP is co-efficient of performance, basically a measure how much energy a heatpump (like a fridge or heating and cooling air conditioner for example) moves compared to how much the compressor consumes.
Not over keen on using a single diode for snubbing the relay coil, this can lead to premature wear on the contacts, as it takes 10-20-30mS longer to open the contacts properly. I use a diode with a matched resistor (normally around 10 x the voltage, so 12V would be 120ohms ish) in series, placed in parallel with the coil. This kills the spike just as quick but also stops the relay from bouncing or re-energising, keeps the opening of the contacts as fast as possible. You can also use a matched MOV but these are more expensive and give little gain over the diode and resistor. the wattage of which only needs to be 1/4 or 1/8. If you are using coils on pneumatics of hydraulics (valves) then dont bother with the resistor, 10-20mS slower wont damage them, in fact it helps control fluid bounce in hydraulics.
It is far too common to see a diode smacked across a relay coil, with no regard for the consequences to the contacts. Often it really doesn't matter but when you have relay controlling something like a motor and frequent cycling is expected, you really want to spend a few moments thought and a few extra cents to be kind to the contacts. _Tranzorb_ type power zener suppressors are another alternative and better than MOVs. MOVs do have a wear-out mechanism whereas the power zener devices don't. The power zeners also have better defined voltage characteristics so you can confidently more closely match the voltage allowable across the relay coil to the voltage rating of the switching device. There's nothing wrong with the D & R method if you have room on the board. You can select the resistor value for any peak voltage you want. You do need to be mindful of the transient power handling ability of the resistor. Thin film types are generally not very tolerant of large transients.
@@d614gakadoug9 yep, used transorbs as well, but another cost premium. Pay ya pennies, make ya choice. Main thing is to not just shove diodes in without thinking about the consequences.
I have a cheap one that came with a mini-kiln. Unfortunately, the simple on/off is not very appropriate so I replaced it with a Raspberry Pi and wrote some PID software (That also does cone firing schedules). I use an even cheaper one with a 400W heater to keep my pipes from freezing in our extension.
Think the COPE setting is for tuning the unit to thermostat or messing with it to raise your max setting. I had to boost this to increase the hotplate temp on the coffee maker. The alarm was driving me nuts!
i work for a company that repairs vending machines and coolers. problem with these controllers is that the compressor relay gets stuck and the compressor keeps running. This results in exploded soda cans and a big mess in the machine.
I once saw a photo of what was supposed to be a power factor correction inductor. It was nothing but a wire embedded in concrete (!) in a small plastic box.
Tend to use them on motorbike tyre warmers, cheap enough ive had to replace a few as they can fail at the screen though board interface. I ended up getting a touch version, there are a few different types all called STC-1000.
"Have you destroyed industrial equipment by clicking random buttons?" No bigclive, I have not. But thanks for warning me about excessive button pressing. My previous girlfriend complained about that in bed.
Interested in what you searched for to find this. I use those cheap ones on incubators for hatching eggs and have only had a few fail in many years. I'd always be interested in a better one esp if cheaper.
The ones I've used are the REX PID Controllers that use a thermocouple, have a billion parameters and are suspiciously ubiquitous and cheap for a precision process controller. They must be used in tremendous quantities in China as you can get a kit with a thermocouple and a ssr for like $20.
used one in an incubator. was good for a season. then magic brown smoke and a lot of eggs to throw out.... i have a vague feeling it was to do with all the fluff. incubators are bad for "lint"... now its got a slightly different external one. direct mains plug. waiting for the fan to blow up next... its starting to sound a bit off after five years of feather sheaths flying around. other one i have is the peltier type. WK....1340? im not hunting through boxes to check! something like that. very good for terrariums and mushroom cultivation... not quite as accurate, 1 degree increments versus 0.1. for what it does thats acceptable. not so good for an incubator though, and i cant see a need for cooling... even if it was 42C the other day...
I suspect COP is the coefficient of performance of whatever HVAC this is used to control. Pure heaters (resistive/etc) are fairly close to 1, good heat pumps are quite a bit higher. It's effectively a measure of efficiency, except calling it efficiency is bad practice because η>1 is one of those things that normally break thermodynamics.
I suspect this is a way older model than the modern generic ones. I have used a few of the generics, once had an issue with a relay, while switching an old fridge. Generic units are made for cooling and heating.
This unit was definitely made for a professional, with separate xformer and relay. Consumers would not want to deal with figuring out how to connect this all up - just give them a unit with everything all in one box so less hassles and less mistakes they can make. Another plus was the sealing up the case to keep out moisture, dirt, etc. What's ironic is that the previous owner needed one for refrigeration, and he didn't know that this one was already set up inside for refrigeration, all it needed was a few wires changed. And as a result, Clive got a bargain!
@@DjResR That could maybe work? Although the hysteresis logic would be backwards. And what is the minimum temperature that can be set? If it's 0°C it might not be too useful for freezing, depending on the specific use case of course.
@@maxine_qIf the minimum time logic applies in both directions, there's no difference in logic . Compressors are used for both heating and cooling in aircondition, so protecting compressors is not a refrigeration-only feature .
that potted transformer is pretty much designed exclusively for 220V AC - i looked up the model YXE1411200192Y. China uses 220V as standard for their grid, but Europe uses 230V - that means the transformer is guaranteed to always run over-volted when imported in Europe and will fail when used for longer time above 240V AC - probably they used the eBay "warranty" / maximum refund window as the time reference for its lifespan, and that is 90 days usually. In areas with solar panels or wind turbines that are injecting energy in the grid that voltage can often rise to 250V and is still considered within the voltage spec tolerances of the European 230V standard (+/- 10%), but can cause a high rate of failure for 220V-only equipment.
many components made with cheap chinesium electronics are only built for 5% over-voltage tolerances (if at all) and this is why they tend to fail much quicker than other equipment. Sometimes even have labels that boast a ton of certification logos on them but they are obviously fake when you open them up - in this case it's easy to tell the fake: it is impossible to have a genuine "CE" European Union logo marking on a 220V-only part thus the "CE" certification mark is obviously fake.
12:43 "they're comin' aff" ×2. The true Scot seeping through the 'telephone voice' there. Has tae be done to make it in TH-cam. Naebdy wid ken whit wir talkin aboot, erwise.
If I had a dollar for each unit that survived the warranty period of the device it was built into, I'd still be waiting for my 1st buck. With the cheap ones the supply dies, with the expensive ones the secondary side 5V cap goes bad and they start drifting badly. I've begun to switch the caps on the new units with 105degC low-ESR units, and that seems to help them go longer.
A "good" ordinary electrolytic capacitor has a life rating of 2000 hours at 85°C and probably doesn't even have a apec for allowable ripple current. When you get into good caps with ripple current and ESR specs and want long life, use the largest can size you can fit (e.g. 25 V instead of 16 V or 10 V). That will invariably get you longer life. Tall skinny caps are usually slightly better than sort fat ones for the same voltage and capacitance. Vibration can be a concern, though.
How are switches multiplexed? Surprised it wasn't software or jumper configurable for heating/cooling though. Would simplify inventory by only having a single unit.
It turned out that COP was for changing the factory default settings to allow easier recovery from tampering. The fourth button is for other module applications.
Clive, do you have any experience with the temperature controllers used in heat presses (the kind used to stamp T-shirts)? I found two menu options on mine, labelled "PAt" and "Pld" (accessed by holding down the "+" and "-" buttons as the press is turned on). "Pld" can be set to -1, 0, or 1 (no idea what this is). "PAt" can be set to any value between 0 and 60 (probably a timer). There's also a "C-F" menu option that (unsurprisingly) switches between ºC and ºF.
I considered that, but it only ranges from -1 to 0 to 1. Seems a very narrow range for calibration. I suppose it's also possible that "Pld" sets the "direction" of the calibration and "PAt" sets the value of that calibration. Which would be a weird way of doing things, as opposed to having a single parameter ranging from -60 to 60. And the fact that the second one goes up to 60 really suggests a timer. It does have other parameters for minimum and maximum temperature, etc., but those are in the "normal" menu. The hidden menu only has those three (PId, C-F and PAt). I did notice an interesting detail; the heating element snakes across the plate and then back again, but has 3 connections (one at each end and one in the middle), which I assume is so they can use the same part for both ~115 and ~230 volts (but it doesn't auto-switch).
I hate it when they use the same resolution for celsius as farenheit. It means the farenheit users get more precision than the celsius users, because a 1 degree F change is smaller than a 1 degree C change.
The reality is that the only thing likely to have well-controlled temperature is the sensor. Everything else in most systems will be at some other temperature, so display resolution is moot. Now if you are using something like a rapidly stirred water bath in a lab and have a thermometer adequate to calibrate the system, then an extra digit would be useful.
Pity there wasn't an option to change between cool and heat thermostat. Would make the unit twice as usable. I've made a box for rising bread by switching the leads on the peltier element in a cooling bag and adding a temperature controller.
It really makes no sense why they don't include that option, it's literally able to be done in software. I get that they might want to sell the two versions just so the installers don't have to set that up themselves and to avoid potential confusion, but then again, why not sell the two versions with the only difference being heat or cold mode set as default? Failing that, since this unit has a changeable relay, you could always swap it for a changeover relay (SPDT) and use the Normally Closed contact instead to invert it! Edit: It just occurred to me that doing that would cause whatever device you're controlling to stay on permanently if the relay or controller ever fail. In that case, also add a second relay in series, with it's coil being controlled directly by the power input of the controller. Obviously it's more complicated and not as practical as just having a controller with a proper cooling mode, but it's an option if it's ever needed
Check the temperature probe for signs of water ingress or wire cracking. Also make sure the wires are routed away from electronic stuff like LED lights.
The COP menu item is likely used to copy the current settings over the "default" factory settings. Generally to do this, you get to the COP entry and then within 3 seconds hit the "OK" button (which in your case is likely the Set button). It will then say "YES" and stores the values to the internal flash as the default values. That's how a similar model I have works, in any case.
Captain! Thanks :)
Its more likely to be "Contactor Operation" ....which means you could use it for cooling.
@@andrewpatterson5349 Why would they code such a feature when the user can just change to an NC-relay? It seemed like there was only two COP-options, 12 and 15. Do you think they are a choice between IEC utilization categories? (AC-12 is control of resistive loads and solid state loads, and AC-15 is control of AC electromagnetic loads)
Could it be to set a security code to prevent the settings from being changed by unauthorized personnel?
@@andrewpatterson5349
That was my thoughts as well. Almost all controllers I have ever worked with allow for heating or cooling operation settings.
How refreshing to see a traditional transformer, instead of the usual self destructing switched mode units normally used these days.
It also seems to be a standard style of transformer too. I found one at my main electronic component supplier.
For those that need it...the model number for the 110VAC version is: SF-102(SH)
TY!
Would that be a different bundled transformer?
@@johndododoe1411
The ones I found do have a different transformer with 110VAC input using this wording on the listing:
SF-102 Thermostat Controller Electronic Temperature Thermostat Freezer US NEW
@@gregorythomas333 So either mislabeled or the refrigeration variant .
@@johndododoe1411
Since I was looking for the refrigeration type I used the word "Freezer" in the search...just adjust the wording for your needs
After many years of tearing electronics apart, Clive comes across one device that intends to call a COP to prevent its fated destruction.
An interesting controller, I like the external transformer and relay connection. Makes it so easy to interface with different control devices - relays, SSRs, contactors.
For a moment I thought the last type of control device you listed was contractors. I was very amused.
The internal transistor and power supply are unlikely to be adequate to drive a contactor. You could, of course, use a small "pilot" relay for the contactor coil.
BEWARE! Some contactors have two coils - a low resistance coil that pulls the armature home and a high resistance coil that keeps the armature pulled. A microswitch that is opened when the armature is pulled opens the circuit to the high-current coil. This is a good arrangement for saving power and keeping the contactor from running hot due to coil current, but it is a rude surprise if you aren't prepared for it.
@@jessstrap2088 if you use a high enough voltage, contractors can also start working
I disagree, if you use high enough voltage, contractors tend to _stop_ working. Sometimes permanently.
7:31 minimum restart time is very useful for heat pumps (which also contain a compressor) - for example Daikin recommends a minimum of 6 minutes between runs.
Very nice for serviceability, especially the external relay.
Also makes it more versatile too. Need it to drive a bigger motor? Get a bigger relay. Want to have a whole bank of these? Get a bigger transformer and run them all off it.
@@ConstantlyDamagedCircuit also works from a DC supply that happens to power a larger control system . It looks like it can even run from an industrial 24V DC system .
@@johndododoe1411 Yeah, built for quality and flexibility-rather than to be the cheapest.
Some times there are setting for different probe types in the hidden menu. so you can change between TC and RTD measurement etc also different TC types.
In over 30 years I can't remember seeing one of those 12v transformers fail. Usual failure on those style controllers in refrigeration applications is the compressor relay sticking on.
HVAC techs often find control transformers burned out from short circuits, as can happen by a homeowner miswiring a new thermostat.
the delay time is also good for recovery from power failures. Setting 1 minute will prevent it chattering on a messy power up. I just had a relay burn out from that very reason.
Just to emphasize the point that other people have made, the external transformer and relay aren't just good for maintenance but also for systems where you already have the appropriate power and something else to switch.
Just for example you can use this as a temperature monitor hooking the power side into a computer interface and the relay side into an ADC or digital readback. In that case you might not want a relay involved at all.
We have similar devices behind the bottom cover of our chilled display fridges at work. I was watching the engineers re-gas a faulty unit once and I believe the defrost side is an element very similar to a grill in an oven, sat in the bottom of a drip tray where the hot side of the pipework is coiled up and sits in with it, presumably to boil off water from condensation as our fridges do not have a plumbed drain on them. In the freezers it will run around the cold side to melt off any build up of ice, but the freezers are connected to a local drain due to the amount of water that will be generated. I also believe the "data" line on the unit is connected to a wall mounted device called a 'Plant Watch Pro' in our shop which monitors the state of the fridges and displays their current temperature and can be programmed to call an engineer if a fault condition occurs or the fridge runs too warm for too long, setting off an internal alarm on the panel which has to be acknowledged by a user who then decides if an engineer is required. Fascinating stuff and I guess most people wouldn't know supermarkets go to great lengths to make sure food is kept in safe conditions (albeit a law requirement anyway lol) Thank you :D Id love to get one of those temperature things to muck about with. Could COP be a short hand of Compressor Overload Protection? meaning after a set time a user thinks is too long for a compressor to run, regardless of temperature set it will shut of power to the compressor for overheat protection? Not sure. x
Completely depends on the system. There is no one defrost system type even on similar equipment, to say nothing of the fact that medium temp refrigeration circuits generally don't even have defrost heaters, they just use air defrost and keep the fan spinning while cycling the compressor off
COP can't mean compressor overload protection the way you explained it, because the compressor may run for much more than an hour after the deicing is done, or after the fridge has been started warm.
The overload protection may only be used following an off cycle, setting the minimum wait time until the next on cycle, in minutes.
Most STC-1000 clones have heat and cool outputs and operate both cycles. This is handy for things like fermentation chambers (for brewing or baking) where you may want to target a temperature that is higher or lower.
Add a couple external spdt relays and you can control a thermoelectric device to behave as both heater and cooler.
Sure, but it would always be running, there would be no delay between heating and cooling.
@@mikeceresini2364 nope! You can set hysteresis and minimum on and off cycles.
Yeah, but there's only one output on this unit, so your first relay is either on or off. The STC-1000 has two outputs so you can set cold and hot points, but the output is via two separate relays.
I may have misunderstood your first message, I thought you were saying it was possible to have this unit perform the same as the STC-1000.
This seems to better than the normal controller being available. A very interesting post, thank you Clive 👍
Oh wow, congratz on the 1 million subs
*COP* _might_ mean *Coefficient of Performance* (of a heat pump), which could be calculated approximately from three temperature inputs, in the model equipped with all three.
nice to see ferrules on the end of multicore cable, on friday i went to change a cracked junction box, ferruled the twisted light cable, only to find then they would not go into the terminals... brilliantly compatibility of products, thanks fixscrew.....
Cool, I have worked with most temperature controllers, like you mentioned some only do a good job at heating or cooling but some can have multiple stages I have worked with some that had 4 stages that can be used for heating or cooling so you could use multiple heating systems or cooling and they also have a hysteresis function so it learns how long it takes to heat or cool an area when you want the best temperature control...
I was contemplating something like this for my AV rack. If anyone wanted the equivalent controller for cooling, it is SF-104S-2.
The Coefficient of Performance (COP) of any heat pump will vary as either the inlet temperature or the heat pumps outlet temperature varies. As the inlet temperature increases from the ground, the COP will also increase. That multiple is known as the Coefficient of Performance or COP. As the temperature warms up outside the COP increases. Compared to electric resistance heat, even at -5 F, a heat pump puts out 2x more heat than a resistance heater using the same amount of energy input, or it is 2X as efficient.
It's interesting that they left all three output channels populated despite only using one. The pads on the right with 0 ohm resistors look like configuration jumpers. Maybe you could enable the additional functionality and outputs just by bridging the correct combination of pads?
On a very similar looking controller by Danfoss the COP parameter is for configuring the compressor timing.
Clive, I just got sent this link and I thought I’d share it with you. It seems like a great source for video ideas, in case you’re running low. I know you’ve already seen some, but others might be new to you.
I love all of your content. Thanks for all you do! 😊
There's definitely no shortage of stuff to make videos about.
Thanks for another great video Clive 👍
Have a perfect day everyone 👋
Its been snowing that HAS to be a good day. Hope your day is full and happy.
Sick little temperature control combo. Wish there was a cooling version
There are cooling versions.
Could you not just swap your load between Normally open and Normally closed on the relay to change if it's effectively heating or cooling?
Yes, but the hysteresis won't work as expected. When temperature became greater than Setpoint It would cool down to (Setpoint - Hysteresis) degrees. Of course you could unintuitively set your Setpoint to (Desired Temp + Hysteresis) degrees and it would behave more like a proper cooling controller.
Still one of my favorite channels. 👍
I figured those circuit board connecrors out the hard way. Had un and redone some connections onto a dimmer a few times to many and it snapped off. I ended up soldering the wire onto the remaining pin which was also my very first soldering attempt. It seems to have worked as it still works fine and hasnt blown up.
Process Tech here. If this is indeed for a heat pump, COP may mean Coefficient of Performance.
For my (company's) money, I use Love and Jumo temperature controllers when I need standalone PID temperature control. They're well documented and that alone is worth the premium.
Looks a nice piece of kit.
I made my sous vide pot using a similar device and a cheap slow cooker. Works great.
Great circuit. I think that I would have been tempted to place the NTC & 10k resistor filtering on the other side of the 22k resistor, but this is not a biggie!
*Summary*
- 0:29 The temperature controller being discussed is superior to generic eBay models.
- 0:56 It has better construction and uses traditional power components and an external high-current relay for easy replacement.
- 0:59 The controller includes a potted 2VA transformer and good filtering on the thermistor input.
- 2:16 It is suitable for resistive heating loads and can control up to three external relays.
- 2:51 The PCB is standard with provisions for two thermistors, potentially a third, a fourth button, and a sounder.
- 0:39 The unit was purchased at a lower price because it was sold as a refrigeration controller instead of heating.
- 4:13 The display shows the measured temperature, and pressing a button allows the user to adjust the set temperature.
- 5:00 Programming features include setting the user-adjustable temperature range, hysteresis, delay start, thermistor calibration, and unit measurement (Celsius or Fahrenheit).
- 6:23 Hysteresis and delay start prevent rapid cycling of loads and reduce stress on equipment.
- 8:30 The video's presenter is curious about the real-world reliability of these controllers.
- 9:12 The transcript details the presenter's examination of the controller's design, functionality, and settings.
- 9:37 The controller is noted for its industrial application and serviceable components.
- 13:39 *Reverse engineering begins*
- Designed as a universal unit for refrigeration equipment
- Has three outputs to switch three relays: compressor, defrost heater, and fan
- Suitable for cold rooms or refrigerated cases in supermarkets
- Controller cycles between cooling, defrosting (heater on, compressor and fan off), and then back to cooling
- Includes a beeper for alarm situations
- AC input converted to a rectified and smoothed DC voltage (14-17 volts)
- Voltage regulation and filtering capacitors provide stable supply rails
- Microcontroller drives the display and buttons via multiplexing
- Supports two thermistor inputs with an option for a third one
- Unregulated 12V output, ground, and data line for remote display/button interface
- Features a programming port
- The circuit includes a transformer, a rectifying bridge, voltage regulator, and filtering capacitors
- Thermistor inputs are heavily filtered to ensure stable readings
- Microcontroller drives the multiplexed display and processes button inputs
- There are four transistor outputs: three for relay control and one for the sounder
- The design includes snubber diodes to protect against voltage spikes from relay switching
- The board is versatile and designed for reliability and serviceability
- Components include a durable transformer, high-quality relays, and a robust power supply
- The unit is designed to be long-lasting with low-frequency power components
- Model SF-101 SH general purpose temperature controller, versatile and reliable
Practically every consumer product sold in the U.S. in the last 40 plus years has been manufactured in an Asian factory which means anyone smart enough to figure out how to set up one of those controllers is very familiar with the centigrade temperature scale as well as the metric system.
No way… i’ve ordered one when your video came out without knowing that you also got one. Need mine to repair a cooled show case.
06:20 - Hysteresis
Very interesting tear-down. Thank you Clive.
-----
I am struggling to understand the difference between controller hysteresis and controller dead band. My tentative, incomplete, and quite likely incorrect understanding is that hysteresis and dead band exist in completely different dimensions, i.e., hysteresis is always-and-only a function of time whereas dead band is always-and-only a function of the process parameter that is being controlled (in this case, temperature).
If that is true, then for an ON/OFF (non-modulating) heater controller:
1. hysteresis is the minimum amount of time that shall elapse between calls for heat; and,
2. dead band is the range of actual process temperatures in which the controller will not change state between ON and OFF.
Helpful comments by trained and qualified instrumentation techs are invited.
Hysterises is the temperature difference between compressor/heater on and off. Dead band is the difference between between being in cooling or heating mode.
Eg. Set at 5C with Hys of 1 and dead band of 2 will give...
6C compressor on
5C compressor off
4C you are in the dead band - nothing happens.
3C heater off
2C heater on
To me hysteresis and dead-band is two names for the same thing.
Minimum time off or on is a different thing altogether.
I thing you should probably use an external with all these small temperature controllers. I removed the internal relay in mine and jumpered the contacts accordingly to use it with a solid stater relay without risking the internal relay failing. I have heard that it is not uncommon for recovered relays to be used in the cheap knock off pid controllers among other things.
(4:23) 10 degrees C in your room? I've now concluded that you MUST be in Scotland...
Are they using the display upside down, to get the led under OUT to be on...
They are using the display upside down and a decimal point as the output indicator.
In HVAC COP is co-efficient of performance, basically a measure how much energy a heatpump (like a fridge or heating and cooling air conditioner for example) moves compared to how much the compressor consumes.
Not over keen on using a single diode for snubbing the relay coil, this can lead to premature wear on the contacts, as it takes 10-20-30mS longer to open the contacts properly.
I use a diode with a matched resistor (normally around 10 x the voltage, so 12V would be 120ohms ish) in series, placed in parallel with the coil.
This kills the spike just as quick but also stops the relay from bouncing or re-energising, keeps the opening of the contacts as fast as possible.
You can also use a matched MOV but these are more expensive and give little gain over the diode and resistor. the wattage of which only needs to be 1/4 or 1/8.
If you are using coils on pneumatics of hydraulics (valves) then dont bother with the resistor, 10-20mS slower wont damage them, in fact it helps control fluid bounce in hydraulics.
It is far too common to see a diode smacked across a relay coil, with no regard for the consequences to the contacts. Often it really doesn't matter but when you have relay controlling something like a motor and frequent cycling is expected, you really want to spend a few moments thought and a few extra cents to be kind to the contacts.
_Tranzorb_ type power zener suppressors are another alternative and better than MOVs. MOVs do have a wear-out mechanism whereas the power zener devices don't. The power zeners also have better defined voltage characteristics so you can confidently more closely match the voltage allowable across the relay coil to the voltage rating of the switching device. There's nothing wrong with the D & R method if you have room on the board. You can select the resistor value for any peak voltage you want. You do need to be mindful of the transient power handling ability of the resistor. Thin film types are generally not very tolerant of large transients.
@@d614gakadoug9 yep, used transorbs as well, but another cost premium. Pay ya pennies, make ya choice. Main thing is to not just shove diodes in without thinking about the consequences.
Very nicely made !
Big Clive with a STC 1000.
Even 20 years ago, a similar electronic device would be quite expensive and much larger and heavier
Love it! Want it! I need to control it with a blackberry pico and C. Ty!
I have a cheap one that came with a mini-kiln. Unfortunately, the simple on/off is not very appropriate so I replaced it with a Raspberry Pi and wrote some PID software (That also does cone firing schedules). I use an even cheaper one with a 400W heater to keep my pipes from freezing in our extension.
Think the COPE setting is for tuning the unit to thermostat or messing with it to raise your max setting. I had to boost this to increase the hotplate temp on the coffee maker. The alarm was driving me nuts!
if you change the relay and connected the load on NC contacts the controller can be used for cooling instead of heating
I like that Temperature controller with a separate power supply and relay.
i work for a company that repairs vending machines and coolers. problem with these controllers is that the compressor relay gets stuck and the compressor keeps running. This results in exploded soda cans and a big mess in the machine.
That's why it makes sense to add an extra thermal safety switch in-line with the compressor as an extra backup.
@01:15 chunky heavy
maybe a small transformer potted with sand!
I once saw a photo of what was supposed to be a power factor correction inductor. It was nothing but a wire embedded in concrete (!) in a small plastic box.
Tend to use them on motorbike tyre warmers, cheap enough ive had to replace a few as they can fail at the screen though board interface. I ended up getting a touch version, there are a few different types all called STC-1000.
Is cop Coefficient of Performance,I just googled it
"Have you destroyed industrial equipment by clicking random buttons?"
No bigclive, I have not. But thanks for warning me about excessive button pressing. My previous girlfriend complained about that in bed.
Interested in what you searched for to find this. I use those cheap ones on incubators for hatching eggs and have only had a few fail in many years. I'd always be interested in a better one esp if cheaper.
The ones I've used are the REX PID Controllers that use a thermocouple, have a billion parameters and are suspiciously ubiquitous and cheap for a precision process controller. They must be used in tremendous quantities in China as you can get a kit with a thermocouple and a ssr for like $20.
used one in an incubator. was good for a season. then magic brown smoke and a lot of eggs to throw out.... i have a vague feeling it was to do with all the fluff. incubators are bad for "lint"...
now its got a slightly different external one. direct mains plug. waiting for the fan to blow up next... its starting to sound a bit off after five years of feather sheaths flying around.
other one i have is the peltier type. WK....1340? im not hunting through boxes to check! something like that. very good for terrariums and mushroom cultivation... not quite as accurate, 1 degree increments versus 0.1. for what it does thats acceptable. not so good for an incubator though, and i cant see a need for cooling... even if it was 42C the other day...
Heat or cold, just a question of using NO or NC on the relay.
Anyone know of a quality relative himidity amd temp controller???? Ty!!!
COP means "Can't Operate Properly"
I wonder if the '3rd thermistor' provision is actually for cold junction compensation.
Closes "quality version" of the STC-1000 is a XR06CX which can pretty much do anything with it's extreme parameter settings.
I suspect COP is the coefficient of performance of whatever HVAC this is used to control. Pure heaters (resistive/etc) are fairly close to 1, good heat pumps are quite a bit higher.
It's effectively a measure of efficiency, except calling it efficiency is bad practice because η>1 is one of those things that normally break thermodynamics.
To clarify, CoP = rate of total heat transfer / power input or Q/P
Clive, have you seen the disposable nicotine devices with LCD displays? Very curious.
I have one with an LED display.
I suspect this is a way older model than the modern generic ones. I have used a few of the generics, once had an issue with a relay, while switching an old fridge. Generic units are made for cooling and heating.
Very cool. Thanks Big Clive.
This unit was definitely made for a professional, with separate xformer and relay. Consumers would not want to deal with figuring out how to connect this all up - just give them a unit with everything all in one box so less hassles and less mistakes they can make.
Another plus was the sealing up the case to keep out moisture, dirt, etc. What's ironic is that the previous owner needed one for refrigeration, and he didn't know that this one was already set up inside for refrigeration, all it needed was a few wires changed. And as a result, Clive got a bargain!
Although it has the circuitry, the software seems for heating.
@@bigclivedotcom
It might be that unknown menu choice you found is to change to refrigeration?
Change the relay contacts from NO to NC maybe?_
@@DjResR That could maybe work? Although the hysteresis logic would be backwards. And what is the minimum temperature that can be set? If it's 0°C it might not be too useful for freezing, depending on the specific use case of course.
@@maxine_qIf the minimum time logic applies in both directions, there's no difference in logic . Compressors are used for both heating and cooling in aircondition, so protecting compressors is not a refrigeration-only feature .
That first one you showed is what Peopoly is putting in their 3D resin printers.
I appreciate your great videos. Some of which I can understand! But…
I’m baffled- in what world is 14°C a “quite high” indoor temperature????
Clive lives in a strange world where temps are concerned, I couldn't manage to live in a house that was 10C.
@@SlartiMarvinbartfastha ha! Maybe he’s nuclear powered. A brief fiddle with the wires and they went up 4°C! 😊
looked it up and not a lot of information on the website.
Whenever I come across any electronic interface with keypad or buttons, I long press random keys to try to find hidden settings or menus.
that potted transformer is pretty much designed exclusively for 220V AC - i looked up the model YXE1411200192Y. China uses 220V as standard for their grid, but Europe uses 230V - that means the transformer is guaranteed to always run over-volted when imported in Europe and will fail when used for longer time above 240V AC - probably they used the eBay "warranty" / maximum refund window as the time reference for its lifespan, and that is 90 days usually.
In areas with solar panels or wind turbines that are injecting energy in the grid that voltage can often rise to 250V and is still considered within the voltage spec tolerances of the European 230V standard (+/- 10%), but can cause a high rate of failure for 220V-only equipment.
My mains seems to read 237V, that's only 7.7% extra voltage. The transformer should barely notice it.
many components made with cheap chinesium electronics are only built for 5% over-voltage tolerances (if at all) and this is why they tend to fail much quicker than other equipment. Sometimes even have labels that boast a ton of certification logos on them but they are obviously fake when you open them up - in this case it's easy to tell the fake: it is impossible to have a genuine "CE" European Union logo marking on a 220V-only part thus the "CE" certification mark is obviously fake.
12:43 "they're comin' aff" ×2. The true Scot seeping through the 'telephone voice' there. Has tae be done to make it in TH-cam. Naebdy wid ken whit wir talkin aboot, erwise.
what is the diameter of the ntc thermocouple, is it about 2/3 mm (to insert in capillary tube of fridge ?)
Throw a scope over data & ground. Wonder if that's an RS485 port?
RS485 would normally use a balanced pair. I think it's just a simple slow serial link.
So no adjustment of regulation parameters (PID)? That's what would have been critical in the application I would have for such a device.
If I had a dollar for each unit that survived the warranty period of the device it was built into, I'd still be waiting for my 1st buck. With the cheap ones the supply dies, with the expensive ones the secondary side 5V cap goes bad and they start drifting badly. I've begun to switch the caps on the new units with 105degC low-ESR units, and that seems to help them go longer.
A "good" ordinary electrolytic capacitor has a life rating of 2000 hours at 85°C and probably doesn't even have a apec for allowable ripple current.
When you get into good caps with ripple current and ESR specs and want long life, use the largest can size you can fit (e.g. 25 V instead of 16 V or 10 V). That will invariably get you longer life. Tall skinny caps are usually slightly better than sort fat ones for the same voltage and capacitance. Vibration can be a concern, though.
How are switches multiplexed?
Surprised it wasn't software or jumper configurable for heating/cooling though. Would simplify inventory by only having a single unit.
COP apparently stands for Coefficient of Performance.
the Data connection by the bridge is probably modbus.
COP could be coefficient of performance?
COP = coefficient of performance for air conditioning?
It's always better looking at spare cable than for it!
COP I wonder if that is continuous operation or possibly a way to cool instead of heat? What is the upper button on the set side?
It turned out that COP was for changing the factory default settings to allow easier recovery from tampering. The fourth button is for other module applications.
There is another interesting one XH-M452. Temp/Humidity up or down.
I think I have one of those modules here.
Could COP be "Clearance Of Parameters" (or something similar), e.g. a Factory Reset?
It may store the current settings as the new factory reset values.
Why is it called a Y1 transistor? (It's a small signal, switching, and audio transistor?)
It's a simple two character code due to the small area for printing. It will be a very standard multi-purpose transistor for general use.
If a change over relay was used, could this control cooling?
Clive, do you have any experience with the temperature controllers used in heat presses (the kind used to stamp T-shirts)? I found two menu options on mine, labelled "PAt" and "Pld" (accessed by holding down the "+" and "-" buttons as the press is turned on).
"Pld" can be set to -1, 0, or 1 (no idea what this is).
"PAt" can be set to any value between 0 and 60 (probably a timer).
There's also a "C-F" menu option that (unsurprisingly) switches between ºC and ºF.
I'm not sure. Maybe for sensor calibration. I've just ordered a basic heat press, so may explore the settings.
I considered that, but it only ranges from -1 to 0 to 1. Seems a very narrow range for calibration.
I suppose it's also possible that "Pld" sets the "direction" of the calibration and "PAt" sets the value of that calibration. Which would be a weird way of doing things, as opposed to having a single parameter ranging from -60 to 60. And the fact that the second one goes up to 60 really suggests a timer.
It does have other parameters for minimum and maximum temperature, etc., but those are in the "normal" menu. The hidden menu only has those three (PId, C-F and PAt).
I did notice an interesting detail; the heating element snakes across the plate and then back again, but has 3 connections (one at each end and one in the middle), which I assume is so they can use the same part for both ~115 and ~230 volts (but it doesn't auto-switch).
that squishy silicone ripping sound drives me wild!
I hate it when they use the same resolution for celsius as farenheit. It means the farenheit users get more precision than the celsius users, because a 1 degree F change is smaller than a 1 degree C change.
The reality is that the only thing likely to have well-controlled temperature is the sensor. Everything else in most systems will be at some other temperature, so display resolution is moot. Now if you are using something like a rapidly stirred water bath in a lab and have a thermometer adequate to calibrate the system, then an extra digit would be useful.
@@d614gakadoug9 Okay but I just made an Arduino meat thermometer with 0.1F resolution because I want it
Pity there wasn't an option to change between cool and heat thermostat. Would make the unit twice as usable.
I've made a box for rising bread by switching the leads on the peltier element in a cooling bag and adding a temperature controller.
It really makes no sense why they don't include that option, it's literally able to be done in software.
I get that they might want to sell the two versions just so the installers don't have to set that up themselves and to avoid potential confusion, but then again, why not sell the two versions with the only difference being heat or cold mode set as default?
Failing that, since this unit has a changeable relay, you could always swap it for a changeover relay (SPDT) and use the Normally Closed contact instead to invert it!
Edit: It just occurred to me that doing that would cause whatever device you're controlling to stay on permanently if the relay or controller ever fail. In that case, also add a second relay in series, with it's coil being controlled directly by the power input of the controller. Obviously it's more complicated and not as practical as just having a controller with a proper cooling mode, but it's an option if it's ever needed
Why is Sinn Fein making a temperature controller?
At least the calibration and the hysteresis values should have a 0,1C° step instead of 1C°.
Should compare an older tv remote with a modern single chip one.
9:25 - is there a confession there?!
The temp controller with the 3 displays is way easier to setup but only a PCB worked great for growing plants 😂
If you want to have power efficiency just use a little 12VDC switching supply. [DC does not matter]
I was using that exact same controller for our aquarium that died two days ago. The temperature reading is drifting all over the place.
Check the temperature probe for signs of water ingress or wire cracking. Also make sure the wires are routed away from electronic stuff like LED lights.
COP? Coefficient of Power? For heat pumps? Idunno 🙃
really like these videos