I am renting a flat (in Germany, in case that matters), and since we moved in, within 7 months, 3 of our kitchen-appliances broke down with bad smell or even smoking.
It did not happen AT ALL in the previous flat!
What could be the reason, and how could we check it?
Thanks!
Best Answer
Within a European apartment, bad wiring causes appliances to shut off, not fry.
Check it with a voltmeter. I suspect you have excessive voltage, due to a lost neutral between the building and the supply.
Generally in Europe, power is distributed as 3-phase "wye" (230V leg to neutral, 400V leg to leg). However, a freestanding home gets 2 wires from the pole, just one phase and neutral. If neutral breaks, power simply goes out.
However, in a multi-unit building, the building typically gets all three phases and neutral. Each apartment gets a different phase and neutral. Now, if neutral breaks, power doesn't fail exactly. Power can still get from phase to phase, via the appliances that are plugged into it. So for instance, power flows from L1, via your toaster, to Neutral, via your neigbhor's lights, to L2. Meanwhile it's also flowing via your other neighbor's PC to L3. This 3-way flow is a marvel of 3-phase, and you can thank Nikola Tesla.
If all these appliance loads were equal, this would actually work. The problem is, the loads are not equal. The imbalance is causing voltage to go up for some people, and down for others.
Imagine a triangle, 400 on a side. Each corner has a pulley. Each apartment has a string that goes through one of the three pulleys, to a knot in the middle. Each apartment pulls on the string in proportion to how much electricity it is using. There is a pin,holding the knot in the middle so it's exactly 230 from knot to corner. Now remove the pin. Now, the knot can be dragged anywhere in the triangle, depending on how hard each apartment pulls on the rope. The length of the rope from knot to corner is your voltage.
When apartments on other corners pull harder than the apartments on your corner, your voltage goes up. And the excessive voltage fries your appliances. So you would see voltages that are not 230V and at different times, roam between 0V and 400V. (Typically 150-300V). Turning on a large load would make the measured voltage dip.
The power company should be contacted immediately.
In my complex (same exact thing but only 2 phases), it took us a week to notice the problem, and 2 hours to get the power company out and fix it.
In the meantime it is best to shut off circuit breakers to any appliances you value.