The electric car is becoming a reality.
In the near future millions of motorists will have to charge
their vehicule at charging stations installed at home,
in buildings and work places, in public car parks,etc…
To ensure safe operation for everyone,
the major players in the industry have created the EV Plug Alliance
Its goal : to promote connectivity solutions that will ensure
the highest level of safety.
The charging plug type 2 or type 3: What is the solution for Europe?
Charging plug type 2 (T2) or type 3 (T3), this choice leads to many discussions regarding both the electrical performance and the safety of the charging system. Let’s try to see a little clearer.
Electrical performance first.
In its press release, Mennekes indicates that the plug T2 is universal whereas the plug T3 would require three different configurations. This is against absolute truth. If the standard 62196 references effectively different versions of the plug T3 (say 3a, 3b, 3c), only 3c plug is considered today in the debate on the choice made for the charging infrastructure Vehicles ; versions a and b are reserved for specific uses, but they contribute to the cumulative experience of the technology type 3.
Both systems T2 and T3 connection therefore offer the same universality of use in mono-phase as in three-phase 16A as 32A. The range 63A is used only for the connector of the vehicle, because at this level of current, corresponding to the fast charge, the cables are permanently attached to the charging spot. There will be thus no 63A socket outlet installed in infrastructure (the ACEA recommends even to start the use of permanently attached cable at 16A).
Approach the safety aspect now:
The approach of both systems of connection regarding safety is radically different. In the case of T2, safety is entirely based on the fact that the plug is off load when the charging circuit is not established. This is true but in case of breakdown of the electronics of command it is completely possible that plug is energized. We are then in front of the most dangerous case: the user thinks he is in security while he is not. It is important to understand that this case is not only theoretical. This defect was reproduced in laboratory and it will occur inevitably when thousands of charging spots will be installed.
Note also that the electronic circuit permitting to switch off the plug is not the object of any technical description, its design is thus left to the free appreciation of the manufacturer, and nothing guarantees its robustness.
To meet the regulatory requirements of 12 countries of the European Union, representing 55% of the population, the designers of the plug T3 integrated from the very beginning of the development insulating shutters of sleeves guaranteeing the level of protection IPxxD required by the standard. This avoids any risk of direct contact with the metal parts under voltage, regardless of the state of the control electronics, at the lowest cost and in reduced dimension. For countries not wishing to adopt this system, the socket T3 could be delivered without shutter while ensuring the quality of the whole. This is what we know in a common way in the field of domestic sockets E/F or Schuko that are distributed on demand with or without shutter.It is important to note that Mennekes now recognizes the need to provide this level of protection IPxxD by proposing in concerned countries an adaptable device fulfilling the function. But, as the plug T2 was not originally designed with shutter, this adjustment is today cumbersome, ergonomically questionable and probably expensive.
Finally, if we consider the number of plugs installed, the plug T3 is already very widely spread (in France and Italy mainly) and as estimated by Eurelectric, the total number of plugs T3 already installed is probably higher this day than the plug T2.
In conclusion, the T2 plug does not offer today a universal adapted solution to the European needs; the real solution for Europe is to work towards evolution of standardized plugs, Type 2 or Type 3, so that one of them is available in versions with and without shutter, to meet the requirements or expectations of each country. The charging socket T3 can be the basis of such a universal solution.