Explanation of how amps are calculated

RobMadDogTurboCow · Tuesday at 12:48 PM

Hi.
My knowledge of electrical stuff wouldn't fill a thimble so looking for some clarification. We moved into a unit that has a gas cooktop which we are considering changing for an induction. Some in the building have got a Miele 7220 (https://media.binglee.com.au/a/5/7/...79f5bc33c4d915d021_KM7220FL___User_Manual.pdf) and this plugs into a GPO so should have max 10 amp. Our building says we can't upgrade/exceed the 10 amp limit so in theory this should be fine. But the specs say it is a 3 zone system and 2 zones have a normal rating of 2300 watts (i.e. 10 amps) and booster of 3000 watts. All 3 zones have a max of 3450 watts (15 amps).
1. Does this mean we could never use the booster (3000 watts)?
2. What happens if we tried to use two or even all three zones at highest setting, or even booster on all 3? Does it mean it will just "share" the maximum 10 amps between the 3 zones and none would really be at 100% usage?
As I said, I am electrically inept so please be kind with the responses.
Thanks.
Rob

newfutile · Tuesday at 2:56 PM

What is a GPO?
It says your can restrict the current to suit what you have available,this will mean a,longer heat up time.
10 amps is not much I think each zone can use 10- 13 amps,you can apply diversity to these.

Avo Mk8 · Tuesday at 8:55 PM

As above. That Miele model has user selectable presets for max input power, which seem to be, for 230V nominal voltage:
3680 W (16A)
3000 W (13A)
2000 W (8.7A)
1000 W (4.3A)
My understanding is that whichever is chosen becomes the max power that the overall hob will take from the supply.
If your supply is limited to 10A, the conservative option would be to use the 2000W setting
Selecting the 3000W option and using multiple pans could create a 30% overload of your 10A circuit, which, depending on how it's protected, might mean circuit breakers tripping etc. Experiments could be done?

So my reaction to your questions:
1. Does this mean we could never use the booster (3000 watts)?
You could select the setting, but I suspect you wouldn't see as big a change in heat as would be the case with a bigger supply!
2. What happens if we tried to use two or even all three zones at highest setting, or even booster on all 3?
They wouldn't heat as quickly as just having a single one on! Once a pan is up to temp the power demand is much reduced, so I think you could continue simmering or boiling several at once without a problem.
Does it mean it will just "share" the maximum 10 amps between the 3 zones
Yes, but possibly in a clever way based on the size/demand from each pan.
and none would really be at 100% usage?
well that's interesting wording. The big advantage of induction is control of power, and the majority of cooking time is spent at controlled 'simmering' or boiling temperatures, not at 100% spewing a volcanic eruption all over the hob.
Could you talk to others in the building to find out how they get on with this model?

At the 2000W setting, I suspect the hob would work adequately, but I doubt the boost will reach full potential. Nevertheless an induction hob should typically boil a saucepan in around half the time of a gas hob (as it's much more efficient getting heat into the pan, as long as you have the right cookware!)

So you might find that even if the Miele induction hob is 'throttled' by a reduced power setting, it is still as fast as your old gas one.

sunray · 2025-06-09T02:14:59+0100

newfutile said:
What is a GPO?
It says your can restrict the current to suit what you have available,this will mean a,longer heat up time.
10 amps is not much I think each zone can use 10- 13 amps,you can apply diversity to these.

I think I've seen GPO being the American General Purpose Outlet,

In which case it would be 1200W max