When I was building my house, I installed an outlet under my service panel which was temporarily connected to a breaker in order to supply our tools while building. I have since removed the outlet but now I need an outlet there again. Since the panel is in the basement, behind hinged wooden panels, is there a conflict with the code if I install a receptacle in that location under the service panel? I could locate a nearby circuit which has less than 12 units on it and wire it into that circuit. Or could I wire it directly to another circuit breaker in the panel? Is a 15A circuit breaker allowed to have two wires connected to it? thanks for the advice.
I myself would not add it to an existing circuit, especially one with already over ten devices.
As long as the hinged panels expose all the electrical components you are OK.
You can put two wires under newer Square D QO & HOM breakers, and most newer Cutler Hammer CH breakers.
Best bet though for a DIY is to pigtail so you are sure.
Sometimes I feel like if I answer any more questions it is like someone trying to climb over a fence to jump off a bridge and me giving them a boost.
Answers based on the 2008 & 2011 NEC.