Placement of the meter or main distribution cabinet

Hello everyone,

we currently have a problem with the placement of the meter cabinet. This was already assigned to a position (wall) in the technical room during planning. The house connection box is already located on this wall and was installed by the installation company without any notice. Now our electrician says that this place is not suitable for the installation of a meter or distribution cabinet and would violate regulations. According to him, these are not allowed to be mounted on a wall that represents an exterior wall of the building. Only interior walls may be chosen for placement. If this is the case, then we have a significant problem. As it was planned, it is simply perfect. We have read all the DIN and VDE standards, and nowhere could we find this regulation. Also, from the network operator, we could not find anything about this in the guidelines. Criteria are described there, but nothing about on which wall the installation must take place.

For your information: The technical room is located in the basement.

Does anyone know about this regulation? Does it even exist?

Turn the tables and ask the electrician where it says that a meter cabinet is not allowed on the outside wall. That's what I do when someone tries to tell me that this or that is not allowed. Just bluntly ask, "Oh really, where does it say that?"

PS: He might be referring to an old standard that was withdrawn because there is an updated one. That happens quite often.