No power Started to defrost some food and microwave suddenly had no power.

One is the power setting used for defrosting food not a button that says defrost.

Microwaves work by friction. They blast water molecules in the food so they move fast, just like rubbing your hands together makes them hot. Some types of microwave in defrost mode actually apply FULL POWER for a short period of time so to make the product warm to the touch. This heat then penetrates down to the core of the food, ensuring full defrost. In your case the heat was sufficient enough to heat the dry paper towel to set it on fire.
Bread is better defrosted on the low power setting as sliced bread is very thin. Items should only be defrosted on the defrost setting that are thick and need to be completely defrosted on the inside. Remember microwaves only penetrate the surface of food, making that hot. Thermal conduction does the rest.
You should never use paper towels in a microwave unless the instructions for doing the food say so. You wouldn't put a paper towel in a gas or electric oven, so don't put them in a microwave.

You read the weight of the food on package (in lbs)
Put the food on a microwave safe plate /container.
Close the door.
Press the Defrost by weight button
Enter the weight of the food. The time will be set automatically.
If you have a defrost by time, just decide on the time duration and enter it

You read the weight of the food on package (in lbs)
Put the food on a microwave safe plate /container.
Close the door.
Press the Defrost by weight button
Enter the weight of the food. The time will be set automatically.
If you have a defrost by time, just decide on the time duration and enter it

either a fuse inside the unit or ?

Hi ifcope2000,

The inverter in your oven is for defrosting. It works on the basis of weight of the food to be defrost. To use the inverter follow the following steps.

First place the food on the microwave dish and then close the door.
Now press Inverter Turbo Defrost.
Enter the weight of the food using the number pads.
Press Start.Defrosting will start. The time will count down. Larger weight foods will cause a signal
midway through defrosting. If 2 beeps sound, turn over, rearrange foods or shield with aluminum
foil.

Atul

Sorry but it sound like a component in the power circuit, transformer/capacitor/diode?.
if you feel capable to do the testing I can guide you