Czech Republic overview of types of plugs and sockets |
In
the early years of electrification the nowadays Czech Republic
and Slovakia were a part of the Austro-Hungarian Empire. From
November 1918 until the end of 1992 the countries were united as
Czechoslovakia. In the 1920s and '30 the country belonged to the top five industrialized states in Europe. Industry was concentrated in Bohemia and Moravia, regions that now constitute the Czech Republic. Current models of Czech plugs and sockets - that are also used in Slovakia - are shown in image nos 1 - 17. Classic material is shown in images 18 - 23. The museum is indebted to Tomáš Drahoňovský and ABB Elektro Praga in Jablonec nad Nisou for donating items 1 - 14. A short history of the company is given below. |
Intro | Already in 1933 the Czechoslovakian
Electrotechnical Association (ESČ) stipulated that from June 1934
earthed sockets must be installed in all new buildings, homes included.
Czechoslovakia was probably the first country in which this
safety rule was made mandatory for all new wiring installations. Poland
followed soon. Initially Czechoslovakia opted for the Schuko system, but finally decided to chose for sockets that have an earth pin (now known as CEE 7/5 standard). Read more about the origin of earth pin sockets on a separate page. |
1 |
CEE 7/5 standard domestic socket, rated at 16A - 250V.
Sockets must have a recess (depth: 14.7 mm). Earth pin diameter: 4.8
mm. Socket earth pin makes contact first when a plug is inserted. Modern Czech sockets have safety shutters, operated by simultaneous entry of line and neutral pin. Shown is an example of the ABB Elektro-Praga Levit® line. |
2, 3 |
Dual socket with a 32ş rotated top outlet. Image no. 3*
illustrates the benefit of a rotated outlet when using plugs with cord
side entry. * image of the Element® line dual socket has been copied from Czech tzb-info site. |
4 |
Socket with lid, rated at 16A - 250V. The socket has
International Protection rating IP 44* which mean that it can be used
among others
in bathrooms. * first digit: protection against ingress of solid objects with a diameter larger than 1 mm; second digit: protected against splash water from any direction. |
5 | CEE
7/6 plug, rated at 16A - 250V. Pin diameter: 4.8 mm. |
6 |
Elektro-Praga
designed in the 1950s a plug to bridge the gap between earthed
sockets used
in Czechoslovakia (see no. 1) on the one hand and the German Democratic
Republic (using Schuko) on the other. This so called joined
plug
complied with Czechoslovak ČSN ESČ 107 standard. It became a
successful
export product. The image shows an essentially identical, but more recent model, that is now better known as a CEE 7/7 hybrid plug. Rating: 16A - 250V. It will be clear that also not earthed 2.5A CEE 7/16 (Europlug) and 16A CEE 7/17 plugs fit in standard Czech sockets. |
ABB Elektro Praga plug 5536.
Rating: 10-16A - 250V; pin diameter: 4.8 mm; cord side entry. |
7 - 8 |
Plug 5536 consists of three parts: (8a) thermo-plastic cast,
(b)
black body
with pins and earth
contact, and (c) top cover. Fig. 8d shows the assembled plug (identical to image no. 7). Cast 'a' has four holes that allow mounting pin body 'b' in four, 90 degrees rotated positions. Images 'd', 'e', 'f' and 'g' show the resulting plugs. To emphasize the different pin and earth contact orientations each plugs is shown with cord entry down. This clever design is the best selling general purpose plug in Slovakia. Information provided by Lubomir Tomik (Nitra, SK). |
Type C 220 V DC 1-pole +E |
Type C1 110V AC 1-pole +E |
Type C2 110 V DC 1-pole +E |
Type D 400 V AC 3-pole +N, +E |
Type K 48 V 1-pole O = pin without wire connection |
Type L 48 V AC 3-pole +N |
9 - 14 | Czechoslovakia had, and both the Czech
Republic and Slovakia still have, a variety of uncommon flat pin*
plugs
and sockets for special purposes. The six types shown below probably
date back to the 1930s. The original Czechoslovak standard ČSN ESČ 153 has been replaced by the Czech standard ČSN 35 4517. * flat pin size: 5.0 x 2.5 mm, 18.5 mm long. Diameter of round pin (type K): 6.0 mm. Each of the six types is rated at 10A - 250V (C, C1, C2) / 440V (D) / 48V (K, L). Specifications of intended AC or DC voltage are given in the images below. Low voltage type K is still used in specific industrial environments where 230 Volt is not allowed for safety reasons. The 48V 3-phase type L is occasionally used in energy storage devices. |
ČSN 35 4517 lookalike material once made by other companies. HNA (Handelsschiff-Normen-Ausschuss), a German shipbuilding standard that dates back to 1917 is similar to type C. However, because of small differences between type C and HNA - see figure left - the two types are incompatible; even applying brute force doesn't help. Stotz-Kontakt model 14219 (see 1939 catalog) is fully identical to type C1. The German company (now part of ABB Busch-Jaeger) has ended production of the model. A 4-pin model made by the Austrian company ELIN has a pin configuration that looks similar to type D; see scheme i in a 1936 catalog. |
Image
nos 15 - 17 show classic appliance couplers. Shown inlets, outlet and
plugs, made by
Elektro Praga, are still on offer for repair of older, still functional
equipment
and appliance cords. The Elektro Praga article numbers are given for
each appliance coupler. Inlets, outlet and plugs are depicted to scale.
The museum is grateful to Matúš Goĺa for
donating the material. |
|
15 | 6A
- 250 V appliance inlet (5913) and connector plug (5816). Plugs have
earth contact strips on opposite sides; see plug side
view. Plugs are not polarized. The models are
identical to couplers made by the German company Kautt &
Bux; see nos 24 and 25 classic
connector page 2. {MG} Flat blade size: 2.0 x 5.0 mm, length: 15.2 mm; blade spacing (center to center): ca. 10.5 mm |
16, 17 |
2.5A
- 250V appliance inlet (5911), matching connector plug (5813), variant
model plug (5823), appliance outlet (5211) and matching male connector
plug.
The variant model 5823 fits in an intlet with a vertical and a
horizontal blade (not in the collection). Also a 'tandem' variant with
two horizontal blades have existed. Both standard and variant
plugs are polarized because they have a single earth clip and power
contacts are positioned off center. The 2.5A appliance couplers were a
unique Czech design, according to Czech norm ČSN 354508. The norm was
cancelled and
production ended in 1995. {MG} Flat blades size: 1.4 x 2.5 mm, length: 12.3 mm; blade spacing: 6.0 mm |
Classic material |
The
museum is grateful to Stanislav Kotula for providing information from
Elektro-Praga catalogs and scanning Kramer und Löbl 1938 10 Amp
appliance connector (image no. 22, left) |
|
|
18 | Bakelite,
not earthed plug, rated at 6A-250V. Pin diameter:
4.0 mm. The type of plug does not fit in sockets installed from 1934.
Therefore it must have been made for replacement in pre-1934 wiring
installations, or
it was meant for export. Plug has art.no. 1372 and the triangular Elektro-Praga logo introduced in 1946. An identical plug, with same number 1372 is mentioned in the 1938 Kramer und Löbl* catalog. In the Elektro-Praga 1950 catalog the plug has art.no. 5402-10. These facts indicate that the shown plug dates to the late 1940s. * pre-WWII electro-technical company that became Elektro-Praga in 1946 (see short history, below). |
19 |
Earthed, 6A-250V plug suitable for sockets with earth pin.
The Czechoslovak standard ČSN ESČ 107 (similar to CEE 7/5-6) became
compulsory in 1934. Pin diameter: 4.0 mm; earth contact accepts 4.8 mm
pins. Shown plug is listed in Elektro-Praga 1963 catalog. (no. 5420-10). {RH} |
20 | Not
earthed 3-way multi-plug rated at 6A-250V. Contacts can accommodate
plugs with 4.0 mm pins only. Plug is mentioned in 1938 Kramer und Löbl
catalog, but shown model has an Elektro-Praga logo and must have
been made (shortly?) after WWII. |
21 | Earthed
3-way multi-plug, rated at 10A-250V. Both power pins and earth pins
have a diameter of 4.8 mm. Elektro-Praga model no. 5320-20, introduced
in 1950. {RH} |
22 |
Appliance connector plugs, rating 10A - 250V. Left: image
copied from Kramer und Löbl 1938 catalog. Right: plug with same
Bakelite housing, but flexible cord guide and earth connection are
missing. Left plug has the common KL logo, whereas the other plug has a
similar logo with capitals H and B. Research has revealed that HB are
the initials of Hans Büllmann. German army invaded Czechoslovakia in 1939. The Jewish Hugo Löbl was dismissed and during WWII replaced by Hans Büllmann. Initials KL in the company logo changed into HB. Production shifted to war industry. A cut down on not strictly necessary materials including plug cord guides, earth clips etc. could have been a possible consequence. |
23 | Earthed appliance connector, rated at 10A-250V. Complies with German standard DIN VDE 49491. Connector has a Czechoslovakian ESČ certification mark that is also shown on plug no. 19 and multi-plug no. 21. Manufacturer: Elektro-Praga, art.no. 1052. Dating: introduced and patented in 1947. {RH} |
a. Logo used by Kramer and Löbl on electrical accessories (until 1940). b. Logo introduced in 1946 for the group of manufacturers of electro-technical appliances. c. Logo on plugs, sockets, switches etc., made in Jablonec nad Nisou from 1960. Found on nos. 6, 15, 16, 19, 21 and 23. d. Asea Brown Boveri logo on products made from 1993. Found on nos. 1, 2, 4, 5 and 9 - 14. Plug no. 7 has both logo 'c' and 'd'. Plugs made by Kramer and Löbl in the 1930s are missing in the museum collection. Suggestions were to find them are welcome. |
Short
history of ABB Elektro Praga 1868. Gustav Kramer and Adalbert Löbl started production of refined glass and crystal lamps and chandeliers in Jablonec nad Nisou (Gablonz in Austro-Hungarian Empire). 1908. With the growth of electrification Kramer and Löbl started production of accessories related to electric lighting, as sockets, plugs and switches. It proved to be a profitable market. Glass production was scaled down and ended in 1924. The company was renamed 'Kramer und Löbl, Fabrik elektrotechnischer Artikel'. Adalbert Löbl's son Hugo joined the company. He promoted strongly the move toward electro-technical material. 1931. Kramer and Löbl introduced the Bakelite molding process in Czechoslovakia. The company became the dominant manufacturer of electrical accessories and exported products to many countries all over the world. 1939. After annexation of Czechoslovakia by Nazi Germany, the company was confiscated. The Jewish owner, Hugo Löbl, was dismissed and replaced by Hans Büllmann. From 1940 production was fully focused on war industry. 1946. After World War II, industry was nationalized in Czechoslovakia. Electro-technical companies were merged and renamed to Elektro-Praga. The plant in Jablonec nad Nisou had the monopoly for manufacturing electrical accessories. Production grew steadily and from the 1960s export started to other countries. 1989. State owned enterprises were privatized. In 1993 Elektro-Praga in Jablonec nad Nisou became part of the Asea Brown Boveri (ABB) concern. |
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