Liquid Boiling Mechanism (W1209 thermostat relay wiring)

Thread Starter

dieforedoras17

Joined Mar 9, 2022
12
Hello,

I m working on a project for understanding of milks boiling process.I will save and graph tempreture data via Arduino Uno(with Micro SD module module and RTC).I m beginner and I m figuring out projects technical requirements step by step.

Component list
D18B20 Water Proof Tempreture Sensor
Micro SD Module
Ds3231 RTC Module
Ardunio Uno R3
Push button/Breadboard/Jumper cables etc.
4.7 k resistor
LRS-50-12(220 V to 12 V AC/DC Adaptor)[4.2 A]
W1209 (Thermostat)[20 A Relay]
Kettle(with 3 strand cable)[1000 Watt]

I prepared interface Delphi and LabVİEW and i am trying to learn fundamentals.I want to control the kettle(1000 W 220v)with W1209.

My recent problem is that i can't connect W1209 relay with 220v kettle.I stripped the cable and I connect Load K0 and K1 but it didn't work.Maybe it is simple wiring for experienced engineering student but i can't figure out this connection by now.How can i find solution for that matter?I'm open to hear your comments.

Kettle wires:
Yellow cable:N
Blue cable:Load
Brown cable:Ground


kablo.jpgw1209 image.jpg
 

GetDeviceInfo

Joined Jun 7, 2009
2,095
You will want to be extremely cautious with this. Make sure the controller is firmly mounted within an enclosure, that the enclosure is grounded, if conductive, and that the supply is fused to the load.
As mentioned, you will need to supply power to heater, switched by controllers relay.
To be honest, with the grouping of the terminal posts, I would pass on this unit. I see on different sites they specify the relay rating at 250 vac, but I wouldn’t be applying that next to a 12v terminal.

What could work is a second power relay, DPST, 12v coil, or an SSR
 
Last edited:

Thread Starter

dieforedoras17

Joined Mar 9, 2022
12
Welcome to AAC.

Exactly how are you powering the kettle?
Thank you.Hence i am an electronical engineering student, I decided to improve myself in this field. That's why I find this site very informative.

I got the power from the plug.I planned to take electricity from the socket and make the switching with a thermostat.I cut the blue wire and connected both ends to K0 and K1 but i didn't work.
 

Thread Starter

dieforedoras17

Joined Mar 9, 2022
12
K0/K1 is just a switch - it does not supply power. You need to connect the 220V AC supply to the kettle via the K0/K1 switch so it can turn the kettle on or off.
I connected one end of the heater to the socket, but I couldn't find which ones from N,Load or Ground to connect to where, although I searched a lot on the internet. The local electrician recommended that I take phase from K0 and give phase K1.But i didn't work.
 

Thread Starter

dieforedoras17

Joined Mar 9, 2022
12
You will want to be extremely cautious with this. Make sure the controller is firmly mounted within an enclosure, that the enclosure is grounded, if conductive, and that the supply is fused to the load.
As mentioned, you will need to supply power to heater, switched by controllers relay.
To be honest, with the grouping of the terminal posts, I would pass on this unit. I see on different sites they specify the relay rating at 250 vac, but I wouldn’t be applying that next to a 12v terminal.

What could work is a second power relay, DPST, 12v coil, or an SSR
Thank you for your answer. Actually, I had a lot of concerns about electrical safety. Therefore I put the wires well inside the pin and tied them with electrical tape. The DPST and SSR that you suggested made a lot of sense.

I think it will not harm the system since there is a zero-pass optocoupler in the internal structure of SSR.I will search for it.
 

Ya’akov

Joined Jan 27, 2019
5,663
Since your wiring looks correct the problem seems to be somewhere else.

First, does the controller light up and appear to operate? Can you hear the relay click when it turns on? Without the kettle wired into the controller check continuity between the two contacts when they are supposed to be on.

Second, does the kettle operate without the controller? Wire together the blue wires that are connected to the controller and test.

Third, confirm that you have continuity at all your attachment points for the kettle. If that‘s OK, carefully check for voltage at the input terminal of the controller
 

Thread Starter

dieforedoras17

Joined Mar 9, 2022
12
Since your wiring looks correct the problem seems to be somewhere else.

First, does the controller light up and appear to operate? Can you hear the relay click when it turns on? Without the kettle wired into the controller check continuity between the two contacts when they are supposed to be on.

Second, does the kettle operate without the controller? Wire together the blue wires that are connected to the controller and test.

Third, confirm that you have continuity at all your attachment points for the kettle. If that‘s OK, carefully check for voltage at the input terminal of the controller
1) Yes, the thermostat(controller)works with 12 volts.Yes,i heard the click when it turns on.I will check contacts,i did not control yet.W1209 have to modes for heating and cooling. I will check modes too.
2) Kettle also works without wired into controller
3) In that matter as you mentioned I suspect there is no continuity in the circuit or contacts.

The point that I got stuck with at the beginning was which wire I should connect to relays K0 and K1. According to what you said, the wires are in the right place.I will do your suggestions step by step.Thank you very much for your consuling.
 

Tonyr1084

Joined Sep 24, 2015
6,891
Is the thermostat rated for the power the kettle will draw? If the kettle is drawing 1800 watts then the question is "can the thermostat switch that large a load?" Two things to understand about the kettle: First is that when it is cold the current draw will be much higher than when it is up to temperature. Second is that when the kettle switches off the heating element is still at full temperature. The temp will drop off gradually, depending on the size of the kettle heating element. So your kettle will experience what I call "Thermal Inertia".

Thermal inertia is when the heating element reaches - lets say 5,000˚F. When it is switched off its hot mass will continue to be hot and heating whatever is in the pot. The element doesn't stop all heating at that moment. If your set temperature is 180˚F and your thermostat shuts the pot off at 180 it's quite likely the pot will heat well past 180. I can only guess, but years back I tried using a toaster oven for curing epoxy potted samples. The oven reached the set temperature but the parts were still burned by excess heat. When I profiled the heat signature I found that the temperature was going way above the set temperature, even though the heating elements shut off at the desired temp. Then the opposite occurred. As the temperature dropped off and fell below the set temp the heating element turned on. But over time the element heated up, causing a sine wave heat profile. Though I set it at (don't recall exact numbers) say - 120˚F the temp would rise to (again guessing from memory) 200˚F. When the set temp was reached I experienced thermal inertia. Then as the temp fell below the set point it would fall a good bit, maybe 100˚F before the temp would start rising again. Like the swing of a pendulum, controlling temp was very hard. I had to find other means to control temp via a much quicker responding heat source.

They sell temp controllers that will heat the kettle. As the temperature gets close to the set point the controller begins modulating the power to the heater. Its heat profile is more like that of a capacitor. The closer to full temp it gets the less power it uses and the slower it approaches final temperature.

So those are the two things I think are worth mentioning: Can the controller handle the power requirements of the kettle and are you accounting for thermal inertia?
 

Thread Starter

dieforedoras17

Joined Mar 9, 2022
12
Is the thermostat rated for the power the kettle will draw? If the kettle is drawing 1800 watts then the question is "can the thermostat switch that large a load?" Two things to understand about the kettle: First is that when it is cold the current draw will be much higher than when it is up to temperature. Second is that when the kettle switches off the heating element is still at full temperature. The temp will drop off gradually, depending on the size of the kettle heating element. So your kettle will experience what I call "Thermal Inertia".

Thermal inertia is when the heating element reaches - lets say 5,000˚F. When it is switched off its hot mass will continue to be hot and heating whatever is in the pot. The element doesn't stop all heating at that moment. If your set temperature is 180˚F and your thermostat shuts the pot off at 180 it's quite likely the pot will heat well past 180. I can only guess, but years back I tried using a toaster oven for curing epoxy potted samples. The oven reached the set temperature but the parts were still burned by excess heat. When I profiled the heat signature I found that the temperature was going way above the set temperature, even though the heating elements shut off at the desired temp. Then the opposite occurred. As the temperature dropped off and fell below the set temp the heating element turned on. But over time the element heated up, causing a sine wave heat profile. Though I set it at (don't recall exact numbers) say - 120˚F the temp would rise to (again guessing from memory) 200˚F. When the set temp was reached I experienced thermal inertia. Then as the temp fell below the set point it would fall a good bit, maybe 100˚F before the temp would start rising again. Like the swing of a pendulum, controlling temp was very hard. I had to find other means to control temp via a much quicker responding heat source.

They sell temp controllers that will heat the kettle. As the temperature gets close to the set point the controller begins modulating the power to the heater. Its heat profile is more like that of a capacitor. The closer to full temp it gets the less power it uses and the slower it approaches final temperature.

So those are the two things I think are worth mentioning: Can the controller handle the power requirements of the kettle and are you accounting for thermal inertia?
Yes,thermostat's rated power is enough for the kettle.Thermostat can switch 220V (12VDCx10A)device.My device consumes 1000 Watts and as you mentioned device will consumes more power when water/liquid is cold. I didn't think that it would draw more current when it was cold, now I will take this into account. I will try to understand the concept of Thermal Inertia and try to control this situation optimally.I did look for cooling or heating pattern.For instance the milk must be in 49 celcius for fermantation.İf i cut power 47 celcius(same milk volume)milk's temp. reach 49.0-49.5 celcius every time that i heat the milk.I will look for the temp controller as you suggest.Thank you for your valuable opinions.
 

Thread Starter

dieforedoras17

Joined Mar 9, 2022
12
After checking the connections and contacts,I managed to run circuit. The problem was the relay.I recommend those who will work with a simple thermostat with embedded software such as W1209 to choose the one that suits them from the modes of the thermostat.
 

MisterBill2

Joined Jan 23, 2018
11,888
The color scheme for the cord, as listed in post #1, is incorrect. Yellow is the safety ground, blue is the mains HOT wire, and brown is the neutral. And the relay on that circuit board will fail after just a few operations.
And there is a lot to be learned prior to even looking at Labview or any of that other list.
 

Thread Starter

dieforedoras17

Joined Mar 9, 2022
12
The color scheme for the cord, as listed in post #1, is incorrect. Yellow is the safety ground, blue is the mains HOT wire, and brown is the neutral. And the relay on that circuit board will fail after just a few operations.
And there is a lot to be learned prior to even looking at Labview or any of that other list.
I got the cable picture in the first post from the internet. My connection is correct because the cables are written on it.You are right,i m trying to process step by step.
 
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