malling wrote:I was not referring to the product as a whole but that specific kettle. If this happened where I live it would be equal to a defective kettle. There is absolutely no chance the way it works would influence any other product on my circuit enough for such behaviour.

15A in US is very different to 15A in Europe, a EKG plus a grinder would easily put you at or near limit in Europe your at half that. I can run this at 10amp and I don't have to turn things off I don't have odd behaviour but then I don't have 110 or ring final circuit.

I think the thing that you are missing is that the wattage on the kettle is the average; not the peak power. You can draw very high currents for short periods of time that will never trip a breaker. You can take another stock Stagg EKG and run it on the same line and the behavior will be the same.

Alright; I'll let everyone get back to the topic at hand. Thank you!

Nick

His circuit is 15amp 230v, there isn't really a chance a 400w and 1200w rating product is going to cause such issues on itself (yes I'm aware it's not peak draw) or going to tricker that. His problem is that it's a ring final circuit, so it behaves differently then most other places in Europe.

You really need to have other stuff on that circuit before you run into issues had it not been ring final. I literally have all lights in my flat, internet, tv, speaker somethings a laptop charging and what not on top of my Flair58, EKG and grinder and it's still not misbehaving on a much lower 10amp 230 circuit. But my electric installation is also very new 2017, we even got ready for 400v we just didn't bother to pay for the last part.

You really need US, english installation or some really old installation like I had in my previous flat with 100 year old wires and fuses, that did in fact mess up when nearing limits as I also wrote very early on.

I'm guessing it's a very sensitive PID circuit in the grinder that's somehow being effected by small fluctuations in the electricity. I would measure the voltage with the kettle cold and it's power both on and off. If it only changes a very small amount then it might be a problem in the grinders electronics.

I doubt the grinder has a PID, if the grinder has adjustable RPM it's likely a frequency regulator IMO.

edit;
I stand corrected, that grinder indeed uses PID for motor control....since it's a DC motor, learned something today

That is a likely explanation, a voltage swing on top of what the PID control is causing and expecting could easily throw off the regulation mechanism causing the control system to over/undershoot and keep adjusting.

fellowproducts wrote:The kettle isn't defective at all; this is how our control system works. The Stagg EKG is designed very differently than other kettles, which is why we are able to get such precise temperature control.

Instead of using bang-bang control, we switch from a relay to a triac during the last 10 degrees of heating. On some circuits you can see the power pulsing depending on what's on the line and how much current is being drawn. Even in my own home I turn off my kettle briefly to run my high current grinders; then once grinding is done I turn it back on.

Just wanted to clear that up. It's really household dependent. Here in the US our breakers are only 15A standard, so running a Stagg EKG plus a high power grinder at the same time is not recommended.

Nick

Hey Nick thank you for confirming this. Is this something that's on the manual? I had no clue about this and have been running my grinders and other equipment alongside the EKG for a couple of years now. Is there a chance that this could have done some permanent damage to these motors?

No damage should occur. We pass all regulatory requirements regarding EMI/EMC, so everything from here on out is mainly the wiring in your home and what your electrical system is spec'd to.

I'd just pop off the kettle for a few seconds while you grind and you'll be in tip top shape.

Nick

There is no way anything plugged into one outlet should affect something else plugged into the adjacent outlet. All that Fellow did was a proper but slightly more expensive implementation and significantly better implementation of a PID controlled kettle.

Marcelnl wrote:I doubt the grinder has a PID, if the grinder has adjustable RPM it's likely a frequency regulator IMO.

edit;
I stand corrected, that grinder indeed uses PID for motor control....since it's a DC motor, learned something today

That is a likely explanation, a voltage swing on top of what the PID control is causing and expecting could easily throw off the regulation mechanism causing the control system to over/undershoot and keep adjusting.

Yes PID BLDC RPM control grinder could theoretically be influenced by change in draws in a ring final circuit if it's overly sensitive or if you are near limit and you product hit peak draw shortly and have some installation issues. As I speculate it could be an effect of those 3 components coming together that tricker the issue.

I just don't see this issue outside ring final circuit or 110v. As there is no chance a product is going to influence another one plugged in, that would require a faulty installation or faulty device.

malling wrote:Yes PID BLDC RPM control grinder could theoretically be influenced by change in draws in a ring final circuit if it's overly sensitive or if you are near limit and you product hit peak draw shortly and have some installation issues. As I speculate it could be an effect of those 3 components coming together that tricker the issue.

I just don't see this issue outside ring final circuit or 110v. As there is no chance a product is going to influence another one plugged in, that would require a faulty installation or faulty device.

fully agree, IMHO a ring circuit is faulty to begin with

Nope, in the US so 110v and no ring circuit and I do see the kettle affect other electronics.