What type of MCB for an induction cooker in 3-phase operation?

[sathornlover]

I ordered an induction cooker online from Ikea in February with 4 plates, 2 of which have booster levels. The appliance consumes 7kWh in the maximum setting.

 

3 weeks ago I asked the electrician who installed our 3-phase PV to connect the cooker to the fuse box. The cooker was already wired for 3-phase operation as described in the manual.

The cooker can now be switched on, but when we select cooking levels 1- to 9, the code "F" appears every 3-5 seconds, which, according to the product instructions, indicates that the cookware is allegedly not suitable for the induction hob.

However, we only use cookware made of stainless steel to which, of course, magnets also adhere and which works without problems on other induction cookers, including an Ikea pot with stainless steel and all have the correct diameter!

 

I took another look in our fuse box and noticed that the cooker was fused with two MCBs 32A by the electrician.

 

Is that correct?

Should the cooker be protected with a 3P MCB instead?

 

For better understanding 3 photos:

 

 

Enquiries at IKEA have not been very fruitful so far. Despite my explicit enquiry, the electrical installation was not considered at all.

The "help" was limited to sending pdfs that I had already downloaded before the purchase and with the contents of which I was very familiar, as well as the never-ending advice that cookware must be suitable for the induction cooker with the following diameters, and so on, Furthermore, in every mail exchange I was asked to send videos in various arrangements of the pots when the cooker is in operation, then always of course the same error code flashing F displayed again ....

 

I would be very happy about any helpful hints here!

[Crossy]

Hmmmm.

 

Is the cooker really intended to run on 2P+N? Can you upload the .pdf files you have please, I would have thought it was intended for 3P (no neutral) operation. Of course, I could be wrong, hence asking for the instructions.

 

I would certainly have used a 3-pole MCB and 2x32A seems oversize for 7kW, again what does the book of words say?

 

@bluejetswhilst we wait for the instructions, any thoughts on this?

 

[flyingtlger]

Maybe it's the Flux Capacitor...

 

 

[sathornlover]

2 hours ago, Crossy said:

I could be wrong, hence asking for the instructions.

 

Thank you for the support many hints you already gave in this forum and of course now in my personal problem!
Now to your question. The sticker on the appliance and the manual only provide these instructions for the electrical installation:

 

 

The complete manual can be downloaded from this link:

manuals matmaessig-induction-hob-ikea-300-black .pdf

[sathornlover]

2 hours ago, flyingtlger said:

Maybe it's the Flux Capacitor...

Thank you also for this advice!
To be honest, I also suspect an appliance fault, but would like to clarify first whether the installation of the appliance is correct.

[Crossy]

OK, it looks like it is correctly connected for 2 of your 3 phases plus neutral, so that one is cleared up.

 

Can you check that you actually have 220V between your neutral and each of L1 and L2 at the stove.

 

If that all checks out, and your pans are definitely compatible (do you have a cast-iron pan you can try?) then I too am suspecting an appliance fault.

 

[sathornlover]

44 minutes ago, Crossy said:

OK, it looks like it is correctly connected for 2 of your 3 phases plus neutral, so that one is cleared up.

 

Can you check that you actually have 220V between your neutral and each of L1 and L2 at the stove.

 

If that all checks out, and your pans are definitely compatible (do you have a cast-iron pan you can try?) then I too am suspecting an appliance fault.

 

Great, thanks, that helps!

 

I don't have a meter in the house, and even though I understand everything we're discussing here, I don't have any practical experience in it, because I usually have everything that concerns craftsmanship and electrics done by the appropriate craftsmen. I actually rule out the possibility that it's the cookware. As I said, my frying pan and a saucepan that I was able to use on another induction cooker without any problems are made of stainless steel and the magnets also adhere very firmly to this cookware. But there is no sign on these cooking utensils that they are suitable for an induction cooker. That's why two weeks ago I ordered a saucepan from IKEA that was explicitly described as suitable for an induction cooker and also had the corresponding label. Two days ago, I suggested to IKEA that they send a specialist at my expense to investigate and, if necessary, solve the problem. Yesterday I received an email that it had been forwarded to the relevant department and that I should be a little patient ...

 

[sathornlover]

Now there is one more thing I almost forgot to mention.

I ordered the induction cooker alongside a sink & traps from IKEA at the very beginning of planning my new kitchen. At that point it was already clear that it was going to be a concrete kitchen, but without the knowledge that this concrete would be stabilised with rebar.

Only during the construction did I realise that this could be a problem for the induction cooker. I asked the craftsman responsible to remove as much of the rebar as possible. Under the cooker and at the back and sides everything is free, but at the front exactly in the insertion area we unfortunately could not remove a steel strut in order not to destabilise the whole underbody. 

 

However, at the time I was afraid that the reinforcing steel could heat up.

Here are 2 photos, could this be the cause of the error message?

 

[gargamon]

18 hours ago, sathornlover said:

However, we only use cookware made of stainless steel to which, of course, magnets also adhere

Sorry. Magnets don't stick to stainless steel. Me thinks this is probably your problem. 

[Fruit Trader]

37 minutes ago, sathornlover said:

Now there is one more thing I almost forgot to mention.

I ordered the induction cooker alongside a sink & traps from IKEA at the very beginning of planning my new kitchen. At that point it was already clear that it was going to be a concrete kitchen, but without the knowledge that this concrete would be stabilised with rebar.

Only during the construction did I realise that this could be a problem for the induction cooker. I asked the craftsman responsible to remove as much of the rebar as possible. Under the cooker and at the back and sides everything is free, but at the front exactly in the insertion area we unfortunately could not remove a steel strut in order not to destabilise the whole underbody. 

 

However, at the time I was afraid that the reinforcing steel could heat up.

Here are 2 photos, could this be the cause of the error message?

 

Work top steel reinforcement would be out of the induction coils range and also outside of the hobs steel case which is also out of range.

 

I can't imagine how acceptable induction can take place within a stainless pot unless it has some kind of iron base or content. Most induction hobs make make a pulsed induction level test before allowing power to the coils. 

[Crossy]

1 hour ago, gargamon said:

Sorry. Magnets don't stick to stainless steel. Me thinks this is probably your problem. 

 

Some grades of stainless are magnetic, many are not.

[sathornlover]

1 hour ago, Fruit Trader said:

Work top steel reinforcement would be out of the induction coils range and also outside of the hobs steel case which is also out of range.

Thank you for your assessment! I would be pleased if this is the case. I have been a bit disturbed by some reports of bent or even singed cutlery trays under the induction cooker.

 

Quote

I can't imagine how acceptable induction can take place within a stainless pot unless it has some kind of iron base or content. Most induction hobs make make a pulsed induction level test before allowing power to the coils. 

As I mentioned in my opening post, all my cookware on another induction cooker works flawlessly!
Stainless steel cookware is actually considered by many sources to be induction cooker compatible,  and this is how many stainless steel products are

advertised at HomePro , IKEA etc. About my "Hemkomst" IKEA pot shown in the photo, you will find the following product description on the website:

"This stainless steel pot has a spout to make …"

"Product details Works well on all types of hobs, including induction hob …"

 

 

 

[sathornlover]

2 hours ago, gargamon said:

Sorry. Magnets don't stick to stainless steel. Me thinks this is probably your problem. 

[Crossy]

And, that pan has the "induction" symbol, it should work 100%.

 

[Crossy]

An Ikea induction capable pot not working on an Ikea hob = get refunds!

 

[gargamon]

1 hour ago, sathornlover said:

All that shows is that the stainless steel is coating an iron core, or it's a cheap grade of stainless steel.

 

Likely the new ikea top doesn't accommodate the grade of stainless in that pan. Luckily for the OP, both were purchased from Ikea so it's on them to resolve. 

[sometimewoodworker]

14 hours ago, gargamon said:

All that shows is that the stainless steel is coating an iron core, or it's a cheap grade of stainless steel.

Actually your comment shows that you have rather less knowledge than you think you have.
 

Grades of stainless steel that are magnetic are not significantly cheaper than non magnetic ones more are they less “good”. They maybe not suitable for a particular purpose, but that only means that you use a different alloy.

[Fruit Trader]

18 hours ago, sathornlover said:

As I mentioned in my opening post, all my cookware on another induction cooker works flawlessly!
Stainless steel cookware is actually considered by many sources to be induction cooker compatible,  and this is how many stainless steel products are

advertised at HomePro , IKEA etc. About my "Hemkomst" IKEA pot shown in the photo, you will find the following product description on the website:

My knowledge of the workings of induction cooker electronics is good but lacking for cookware. 

 

A few tests reveal most stainless steel cooking pots to be highly magnetic some more so at the base with a few showing only mild attraction. I have also found aluminium pan with steel inserts in the base.

 

All induction cookers make a test for the presence of an iron circuit before allowing full power. It is quite possible that your cooker is failing to detect within the low end of its acceptable range and maybe faulty. Most induction cookers use rectified raw mains power directly so it would be a good idea to check that your two phase supply voltage is healthy when the cooker is on load.

[sathornlover]

On 7/18/2023 at 3:28 AM, Crossy said:

Can you check that you actually have 220V between your neutral and each of L1 and L2 at the stove.

I was able to take a measurement today

There are 229-231V at the sockets.

The cooker itself:

First measured phase off 197.9V on 198.6V;

Second measured phase off 198.7V on 198.8V

 

 

 

Surprisingly low values what explanations could there be for this?

 

But after the third attempt to determine the voltage under load, crackling noises were to be heard, at the latest now it was time to check the contacts and indeed it felt a bit loose ... I could do without further measurements - all is well!

 

Thank you very much!????

[sathornlover]

4 hours ago, Fruit Trader said:

My knowledge of the workings of induction cooker electronics is good but lacking for cookware. 

 

A few tests reveal most stainless steel cooking pots to be highly magnetic some more so at the base with a few showing only mild attraction. I have also found aluminium pan with steel inserts in the base.

My knowledge of cookware for induction cookers is also rather rudimentary.

However, what you write about this is exactly the same as my experience!

 

Quote

All induction cookers make a test for the presence of an iron circuit before allowing full power. It is quite possible that your cooker is failing to detect within the low end of its acceptable range and maybe faulty. Most induction cookers use rectified raw mains power directly so it would be a good idea to check that your two phase supply voltage is healthy when the cooker is on load.

Thank you for these explanations, which are also easy for me to understand and helpful as well, and your last assumption was not wrong ,-)

 

Of course, thanks also go to all the others who supported me with their helpful suggestions, expressly except IKEA because apart from PDFs and excuses and now 3 days of silence, not much really came, after this after-sale experience we have considerable doubts about the value of the 5-year warranty promise in an actual warranty case at all …

 

At least from the first impression, it seems to be a good device at a fair price!

 

[sathornlover]

2 hours ago, sathornlover said:

except IKEA because apart from PDFs and excuses and now 3 days of silence, not much really came, 

That was a bit hasty my doubts were fortunately unjustified IKEA just wrote to me:

 

"We would like to inform you after consideration that our team will deliver a new MATMÄSSIG induction hob to your home for replacement.

And they will take your old induction hob back to IKEA. Could you please disassemble it for them to take back?"