I asked this before, but can not find the answer.. I am installing a 150 amp service, and originally was putting the breaker box etc in a 1/2 bath.. and was told, that is not proper.. So, I can install same unit, opposite wall, but will be outside, under a totally dry balcony type place, and I think, I was told that is OK to install it outside, dry, accessible etc, and that some people don't like that, but it has been allowed in the US for 100 or so yrs, and no problem..? Did I dream this?

Bob, you'll get a better answer by sending this directly to tkrussell. He's on the member list near the top. You can have your box in a room with plumbing. It doesn't matter if something has been allowed for 100 years its what's the current code that's most important. Recent changes to the electric code call for ARC faults in bedrooms and carbon monoxide detectors outside bedrooms. Changes are made after the old code kills a few of us.

Now seeing the question, saw a PM first. Correct, NEC does not allow a service or panelboard in a bathroom. If the outdoor "dry" location is not subjected to a driving rain, or any rain for that matter, then it should be fine.

I am not sure about what was allowed for 100 years, locating a panel in an outdoor dry location? As long as it is dry then fine. If not, then the panel will need a raintite enclosure.

Since there is no code to follow where your at, why the worry about small details such as this?