Discuss Updating 1982 Pre-fab building with fuses & no grounding in the Electrical Forum area at ElectriciansForums.net

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Hello,
I have a flat/apartment in a building as described in the subject. I am wondering what to do about the current and additional outlets to have them be safe for kids.

The options:
-Replace fuse box with circuit breakers
-Run ground wiring and connect it to neutral at the junction boxes
-Run ground cables and connect it to whatever there is in the main apartment/flat box(whether it be neutral or a ground)

I am wondering if it makes any sense to install circuit breakers if there is no proper grounding coming up from the basement’s main electrical box.
A previous 1930’s apartment/flat was renovated by an electrical firm where they ran ground to the apartment/flat’s main box and connected it to neutral. The current grounded outlets (a couple in the flat/apartment) have ground connected to neutral at the outlet. Note that the lights and outlets are combined together on the same fuses.
 
I assume this is in Finland and from other posts from similar nations it is not uncommon for the neutral to be used as a shared neutral/ground. You may need the advice of a local electrician.
 
I assume this is in Finland and from other posts from similar nations it is not uncommon for the neutral to be used as a shared neutral/ground. You may need the advice of a local electrician.
Yes, the more local electricians I ask, the more opinions I get. So I thought I may as well ask here for some opinion and explanation/recommendations.
 
It is a thorny subject. Obtaining a surrogate ground connection from the neutral at individual outlets and lights is a form of protection known as 'TN-C', i.e. one wire serves both the function of neutral and ground all the way along. It enables you to obtain something like a ground where there is none, which should improve safety so long as the connections are all good. However, if just one connection of the shared neutral/ground fails, it becomes highly dangerous as all the metal parts of appliances beyond it that are supposed to be grounded actually become live with 230V, since the current that should be returning along the neutral cannot do so.

Some regulations such as those in the UK more or less ban this method outright within the wiring of the building (although a combined neutral/earth conductor is normal for energy supply systems to the building, in TN-C-S supplies). Although used in the distant past, a connection between the ground and neutral terminals of a wall outlet would be considered a serious breach. Yet, I remember doing exactly this in Germany 25 years ago!

A separate ground conductor from the outlets to the main panel is a much better idea, since all but one of the possible break points in the shared conductor are eliminated. This is standard practice in the USA. As mentioned, you should check the local regulations as most have at least guidance, often very specific prohibitions, as to what use may be made of TN-C wiring.
 
It is a thorny subject. Obtaining a surrogate ground connection from the neutral at individual outlets and lights is a form of protection known as 'TN-C', i.e. one wire serves both the function of neutral and ground all the way along. It enables you to obtain something like a ground where there is none, which should improve safety so long as the connections are all good. However, if just one connection of the shared neutral/ground fails, it becomes highly dangerous as all the metal parts of appliances beyond it that are supposed to be grounded actually become live with 230V, since the current that should be returning along the neutral cannot do so.

Some regulations such as those in the UK more or less ban this method outright within the wiring of the building (although a combined neutral/earth conductor is normal for energy supply systems to the building, in TN-C-S supplies). Although used in the distant past, a connection between the ground and neutral terminals of a wall outlet would be considered a serious breach. Yet, I remember doing exactly this in Germany 25 years ago!

A separate ground conductor from the outlets to the main panel is a much better idea, since all but one of the possible break points in the shared conductor are eliminated. This is standard practice in the USA. As mentioned, you should check the local regulations as most have at least guidance, often very specific prohibitions, as to what use may be made of TN-C wiring.
Thank you. It sounds like the farther the surrogate ground connection is from the outlets & lights (none of my ceiling lights have a ground anyway so I don’t care about those) the lower the chance of live voltage on ground lines & appliance frames.
I am 80% sure that there is no ground wiring coming up from the building electrical supply to the apartment/flat main panel so the best solution may be surrogate grounding to neutral at the main panel. A second-best option may be to surrogate ground to neutral at the junction boxes (of which there are 6 or so) which distribute to the lights and outlets through the apartment/flat. Do I understand correctly?
 

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