Museum of Plugs and Sockets logo, small CEI 23-50 standard
Italian plugs and sockets
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Comitato Elettrotecnico Italiano standard 23-50 plugs and sockets are used in Italy, Chile, Cuba, El Salvador, Ethiopia, Libya, Syria, Tunesia and Uruguay.
CEI 23-50 (first edition in 1995) has replaced the CEI 23-16 (1971) standard. Section VII of the standard relates to 10A and 16A plugs and sockets.
Type J profile Related galleries:
uncommon types
heavy duty types


VIMAR CEI 23-50 socket, 10A CEI 23-50 socket for 10A and 16A plugs Contacts of Italian 10A / 16A socket Italian 10A and 16A connectors, CEI 23-50
Italian 10A and 16A plugs, CEI 23-50 BTicino corner plugs, 10A BTicino corner plugs, 10A 16A CEI 23-50 adapter for 10A plugs

In the first half of the 20st century two voltages were commonly available in homes (at different tariffs): 110 Volt for „luce“ (light) and 220 Volt for „forza“ (power). Different plugs were used for 110 and 220 Volt to prevent incorrect connections: 10A plugs with 4.0 mm pins, 19 mm apart for 110V and 16A plugs with 5.0 mm pins, 26 mm apart for 220V (information given by Markus Stöllnberger).
Distinction in voltage does not exist anymore, in favor of 230V, but the difference between Italian 10A and 16A plugs still exist.

1 Classical example of a CEI 23-16 (now 23-50) standard 10A socket. The example shown is a VIMAR company, type SICURY socket. Sicury refers to a shutter that prevents accidental contact with line pins. Vimar was the first Italian company to offer this safety provision in 1968; details are shown below. Nowadays safety shutters are compulsory.   {SL}
2 Socket that can accommodate both 10A and 16A plugs (see no. 6). The left hand outlet has quite common bipasso or bivalente (dual use) figure of eight shaped slots. The larger (5.1 mm) diameter 16A slots have a 26 mm spacing; the smaller (4.5 mm) 10A slots have a 19 mm spacing, which is also suitable for Europlugs. Brand name: Bticino.
3 The Bipasso type socket no. 2 allows separate wiring of the 10A and 16A outlets. They can be connected to respectively a 10A and 16A fuse in the main fuse box of the house. However, it is also possible to interconnect the two connector blocs. 
Note that Italian CEI 23-50 plugs and sockets are not polarized, because of the symmetrical arrangement of the slots
. That means that the position of brown (line) and blue (neutral) wires can be swapped.
4 10A and 16A connector plugs. 16A models have 'dual use' shaped outlets. Manufacturer: Scame.
5 Italian 10A and 16A plug. It is compulsory that the basal part of power pins have an isolating sheath against accidental contact with line parts. Pin diameter of 10A plugs is 4.0 mm; 16A plugs have 5.0 mm pins. Manufacturer: Scame.
6, 7
Examples of two models of 10A plugs of which the pin position can easily be changed from top to side (compare top and bottom images). The thickness of both housings is only 15 mm. The disassembled model (see no. 8) shows the elegant simplicity of the design. These 'Corner' models are developed by the Italian Bticino company.
8 Adapter for making 16A sockets also accessible to 10A plugs. Manufacturer: SRS (abbreviation of an unknown company)

Italian universal socket VIMAR multiple type socket
VIMAR series Mascot, socket 'universale' Italian multiplug for 10A, 16A and Schuko plugs

4BOX 3 in 1 socket
4BOX 3 in 1 socket
4BOX 3 in 1 socket with 10A and 16A plug
4BOX 3 in 1 socket with Schuko plug

Italian grounding system differs from all other standards. Adapted sockets have been designed to bridge the compatibility gap between Schuko (CEE 7/4 and 7/7) plugs and typical Italian sockets. Examples are shown of three Italian manufacturers. These multi-purpose type of sockets are becoming increasingly popular in newly build accommodations.
9 'Universal' socket for Italian 10A and 16A plugs, as well as earthed Schuko type plugs. The diameter of the inner (10A) slots is larger than the 10A slots in sockets nos. 1 and 2, otherwise it would be impossible to insert a Schuko plug (pin diameter 4.8 mm; spacing 19 mm). Manufacturer: BTicino.   {WaO}
10, 11 Two examples of VIMAR type 'universale' sockets, suitable for Italian 10A and 16A plugs (indicated with I), Schuko plugs (D) and unearthed flat blade plugs (USA, but 230V). Socket no. 11 also accepts British BS 4573 shaver plugs (GB). This Mascot series socket has a 220V label, that can be replaced by a 110, 127, 160 or 240 Volt label.   10: {WaO};   11: {MSt}
12 3-way, 'triple use' multi-plug for Italian 10A and 16A plugs (top and side entries) and a Schuko plug (top entry only). Although this multi-plug is meant for a 10A outlet, it also allows 16A plugs (either CEI 23-50 or Schuko)*. Schuko plugs cannot be inserted in the two side entries, because of insufficiently large diameter of those 10A slots. Manufacturer: Scame.
* from 2014 it is no longer allowed to produce and sell 10A multi-plugs or adapters that accept also 16A plugs.
13- 16 The Italian company 4BOX, based in Milano, has designed a socket that can be used for CEI 23-50 10A and 16A plugs, or a CEE 7/4 (Schuko) plug; see respectively image no. 15 and 16. The two flexible earth clips - essential for Schuko plug earth contact - seems to hinder the insertion of Italian plugs (see image no. 14). However, an ingenious mechanism pushes the earth clips aside when a 10A or 16A plug is inserted. Up to two Europlugs can be inserted also.   {WeO}

CEI 23-50 10A 3-way multi-plug

CEI 23-50 16A 3-way multi-plugPlugs made of galatite

17 10A multi-plug with three 10A outlets. Manufacturer: Scame.
18 16A multi-plug with four 'dual use' outlets. Manufacturer: Scame.
19 Small plug (33.4 x 12.5 x 19.8 mm) designed for replacement of classic lamp cord plugs. The plug has been made of galalith, a synthetic plastic material, based on casein and formaldehyde. A block of galalith can be cut, drilled, carved and dyed. Because it is not possible to mould galalith, the plug has a simple, one piece body. Wiring has to be done by unscrewing the partially insulated pins. Any form of cord tension relief is not possible.
The Italian shop Punto Luce offers (2016) galalith plugs in four colors: marrone (chestnut brown), grigio (grey), oro (gold) and ivorro (ivory). Rating and manufacturer are not indicated. Plugs have no certification mark.   {MSt}



Bticino not earthed 10A socket
Bticino not earthed 10A socket
Bticino not earthed 10A socket
Obsolete Italian 16A socket without earth

ETF not earthed 2-way multi plug
ETF not earthed 2-way multi plug
ETFnot earthed 2-way multi plug, inside
BTicino and TGM logos

20 - 22
Obsolete type not earthed 10A socket that was a part of the Bticino Domino series. The two brass contacts are kept in place in a small porcelain block that is fixed to the wall plate by a single screw. A simple but effective design. Rating: 6A-250V AC or 10A-125V AC. The note "GARANTITO 5 ANNI - 1956" suggests that guarantee ended in 1961. The Bticino logo that was used at that time is shown in image no. 26.   {WN}
23 Obsolete type 16A socket without earth. It was part of the Btichino Piuma series that was produced from the mid 1950s to late 1970s. See caption to image no. 26 for details about the Btichino company.   {SL}
24 - 26
Adapter plug with two outlets. Rating: 110 - 220V / 200-W. The inside (image no. 26) explains the very low capacity of 200 Watt. The adapter is meant for festoons of intermittent decoration lights; for example in a Christmas tree. The higher the wattage the faster lights are switched on and off.
The adapter is patented (brevettato) by an unknown and probably no longer existing Italian company ETF. Another unknown, TGM logo has been found at the inside, see image no. 27.   {WN}
27 Top: BTicino logo found on socket no. 20. It was introcuced in 1974 when the company name changed to Bassani Ticino.
Bottom: Unknown TGM logo found on the ETF adapter plug no. 24. T.G.M. S.r.l. is an Italian manufacturer of electric cables, founded in 1986. It is questionable whether the adapter TGM is the same as cable supplier.


Logos of BTicino, Scame and Vimar


The brothers Bassani founded 'Ticino Electric Switches' in 1936. In 1948 the company was renamed to Bassani SpA. In 1974 the name changed to Bassani Ticino (see image no, 23). In 1989 Bassani Ticino became a part of the French Legrand group and the name of the Italian division was shortened to BTicino (usually written as bticino or Bticino).

Giovanni Scainelli and three friends founded Scame (Scainelli Materiale Elettrico) in 1963 in Parre (province Bergamo). First insulated nails to fasten electrical cables were produced. After that came a variety of electrical installation materials. From 1990 the company name is Scame Parre S.p.A.

Founded in 1945 by Walter Viaro and Francesco Gusi in Marostica (province Vicenza). In 1968 Vimar's safety shutters were patented (see below). Soon it became the Italian market standard for safety shutters. In 1975 Vimar filed the first patent for a multi-standard socket outlet: Bpresa.

Figure from Vimar's patent 61549, granted on March 15 1968. It shows the
mechanism was patented to close automatically access to socket contacts when a plug is pulled out.

When plug is inserted:
plug pins rotate shutter no. 2 and contacts are accessible.

When plug is pulled out:
spring no. 3 brings shutter back in position that blocks access to contacts.

Vimar 10A socket shown in above image no. 1 has this type of safety shutter.

Source: Vimar history.
Figure from Vimar's patent 61549


Magic 16A plug, small
Uncommon plugs and sockets
The Italian company BTicino has developed
a series of 10A and 16A, polarized plugs and sockets.

Click here for details.

Heavy duty types
Vimar has a single phase plug for 20A similar to the standard 16A type. For heavy duty purposes BTicino offers a polarized 10A three-phase type.

Click here for details.
Vimar 20A plug_small


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