When building world devices what wall voltages should you expect

mainspower

I want to build a dishwasher safe toaster (more details in other questions), So Simplicity of design is a must. Fortunately toasters are among the simplest of electrical devices consisting of nothing more than a switch and a couple really big resistors called heating elements (one on each side of the bread). I figure I can ignore 440/277 systems and focus just on systems that have a 110 or 220 volt standard. Unfortunately there seems to be significant variation within each range. For example I have seen 110v, 115v, 117v, and 120v secondaries on transformers targeting 110v devices before we get to line loss. Similarly I have seen 220v, 230v, and 240v transformers. When building a device for the world market what are the highest and lowest voltages you would reasonably expect to see from the wall in each of these ranges?

Best Answer

10% less than 100V is 90V, and 10% more than 240V is 264V. This is why 86V to 264V is such a common range, and the one commonly accepted by devices that connect to line power.