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EFVA, Main improvements developed in France, in brief:

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North American vs. French:




Main improvements developed in France, in brief:

The differential sensitivity of the device associated with the main breaker was soon increased from 650 to 500 mA.

It was imposed as overload current protections are grouped in a table at a centralized location.

The protective earth conductor (PE) was made mandatory for certain room circuits where the flooring was conductive (for circuits outlets and lighting).

Now the PE is compulsory for all circuits yet the codes states that all conduits must contain a PE conductor.


- In the 1980's, significant material changes incurred:



These changes had also targeted architecture of the protections. It was imposed that the neutral for each circuit returned back to the protection device via the terminals provided. Live (phase) is protected by overload current protection, the neutral is interrupted by a protection switch when triggered or when opening the fuse switch.


= It is the end of the neutral bus in the French electrical panels:



..Protections before the 1980's:.......Protections after the 1980's:





Since the 1980's, the separation of the neutral has permitted to identify more precisely the faults in electrical installations:


Protection against indirect contacts (Parallel Arcs Phase to Ground) after the 1980's:



1 - Insulation fault (parallel arcs) here, in the outlet.
2 - The independent ground electrode evacuates a quantity of current resulting from the insulation fault.
3 - The differential associated with the main breaker detects the difference and cuts off power in an instant, by a value of 230 Volt x 0.500 Ampere = 115 Watts.



In 1991, high-sensitivity differential devices (30 mA) were imposed.


The initial aim was to strengthen protection against direct contact. Initially, all the outlet circuits and all the bathroom circuits (outlets, heating, and lighting) were equipped. Generally, these devices were associated with panel switches and they incorporated the 30 mA differential.


Electricians then massively used these devices, generally beyond the minimum standards required for two main reasons. Aware of the security provided to existing electrical installations, electricians often installed these devices offer their clients during troubleshooting. Placing at the head of the installation, such 30 mA differential provided a shared protection against direct contact but also a serious strengthening of the prevention of fire risks:








Indeed, the 30 mA RCD (as it is called in the UK) limits the value of insulation faults (or parallel arcs) : 230 V x 0.03 A =
6.9 Watts.



Protection against indirect contacts (Parallel Arcs Phase to Ground and Neutral to Ground) after the 1990's:




1 - Insulation fault (parallel arcs) here, in the outlet.
2 - The independent ground electrode evacuates a quantity of current resulting from the insulation fault.
3 - The differential device 0.03 Amp. detetects the difference and cuts off power in an instant, by a value of 230 Volt x 0.03 Ampere = 6.9 Watts.


Today these devices are present on all circuits. This means that a 30 mA HS differential device is located upstream of several overload current protections. The electrical safety standards imposed the installation of the 30 mA RCD, which means one must now install 2 to 4 per dwelling based on its square footage:





At the same time, for public buildings, it was recommended to lower the sensitivity of differential protection from 0.5 A. to 0.3 A. for all circuits. (Except for outlet circuits and some specific circuits which should be protected at 0.03 Amp). The aim was to prevent fires initiated by insulation defects or parallel arcs, limiting the value of these defects to 69 watts.




"Parallel Arcs" between Phase to Ground, or Neutral to Ground

"Parallel Arcs" between Phase to Neutral




There are examples of different terms that describes the same phenomenons.

An arc is the result of a failure somewhere which lead to a contact. For French and Europeans electricians the arc is only the consequence and not the origin of the problem.

A "parallel arc" between phase and PE or neutral and PE is the beginning of what French and Europeans electricians call a "lack of insulation". The arc between the phase and the PE is detected by the differential protection since the 1960s in France. The 30 mA differential protection used heavily since the 1990s have helped to prevent these defects in insulation or "arcs in parallel" for very low values of intensity and also in most cases, between neutral to PE.

A "parallel arc" between phase and Neutral is called in France and most of Europe "Short-Circuit".



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