Hey everyone, I was cooking a spaghetti squash. Set it for 10 minutes came back to microwave shut off. I thought it might be due to putting a big glass pan in there and burning out the turntable motor. I checked the fuse and it was blown. Got a new one. Awesome comes on, but once you actually start to cook it blows the fuse again. I saw a post about checking the door switches. I tested with a multimeter and they look ok. Is there something else i can look for? Thanks in advance!
Be very careful inside a microwave oven. The Magnatron tube runs on a very high voltage and usually has a high voltage capacitor in its power supply. It could injure you if the capacitor is holding a high voltage charge or you try readings with it trying to power on.
Did you use the same type of fuse? The original fuse maybe a slow blow. To allow for the initial current surge when it powers up. The replacement should be the same current rating, voltage and normal or slow blow, depending on what the original one was.
It may have a power supply or Magnatron tube issue that you could not safely troubleshoot if you are not experienced.
Have you done a web search maybe for its model number and see if others have found some typical causes for that model?
I would also confirm what else, if anything, is on the circuit protected by this fuse. Is it possible that there is a recently installed device drawing enough current, when added to that of the microwave, causes the power to exceed that which your circuit can provide?
I have a handy gadget (called a “killawatt”) which measures current consumed by a plug-in load or appliance. You might try one of those to get a sense of whether your microwave is drawing a lot of power. I had this in one of my rental properties, where (for whatever reason) the microwave was drawing over 20 amps. I replaced it and all is well.