In Germany, where these “balcony solar” devices have been approved for years and seem to be the most popular out of any country, the panels have all kinds of safety mechanisms. One of them is a mechanism that shuts of the power coming from the panel if it detects that line power has been lost. It seems that this is what would prevent it from shocking electricians working on lines that they think are unpowered. This article goes into details about the various safety mechanisms on these: balkon.solar/…/how-does-plug-in-pv-in-germany-wor…