Why are AC adapters (wall warts) designed to block adjacent AC outlets?
The AC adapters for a lot of equipment seem to be specifically designed to block the AC outlets around it (this is in the US).
Is this a safety feature to minimize the power to that outlet or just lack of common courtesy?
Clarification: I am NOT asking how to "fix" the problem, but why it exists in the first place. Most of the fixes comprise of adding more wires to a problem which I don't understand why it exists in the first place.
NB! Question is not - What is an AC adapter? There sure is bad/lazy design out there but some adapters seem to be
"specifically designed to block the AC outlets around it"
. Why would that be? Since
"There is no need to limit the current from the output, as most such devices handle low power levels, if compared to an iron or a room heater."
Please see the attached picture of the AC adapter with "ears" to prevent the use of nearby outlets:
The kind of adapter you are referring to is called a wall wart. To quote the article referenced :
One of the major advantages to a wall wart has to do with preventing overheating to both the power source and the device that is receiving the power. Because the wart proper is removed from the equipment that receives the electrical current, it is possible to maintain a proper temperature at both ends of the device. Many models of the wall wart are manufactured with built in thermostats that shut down the unit if a malfunction takes place and the wart begins to overheat.
The wall wart hence has to accommodate for all the components needed to the switching and matching and also accommodate for the transformers size which is required to handle and do the switching. The larger the size of the transformer, the larger and heavier the adapter thus blocking up the surrounding area making it difficult to put in other outlets.
Here are two examples of inbuilt transformers for linear and switching power supplies.
That said its pretty bad design and there are a lot of complaints about how the system was initially designed.