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Czech Republic and
Slovakia three phase plugs |
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| Until the 1990s 16A and 25A three-phase
plugs, characterized by a row
of four or five flat pins, were commonly used in Czechoslovakia. The
type, known as Flako (German abbreviation of Flach Kontakt) was
used also in Austria, Germany, Netherlands and Poland. From the 1990s Czech and Slovakian electro-technical companies switched to IEC 60309 three-phase plugs and sockets, but for some time a limited production of 16A Flako plugs continued to support older facilities. Plugs shown in image nos 1-3 are examples of the last production series. |
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| 1 | 16A - 380V
three-phase plug, without Neutral contact. Model no. 3632-20*. It is
not indicated which of the three shorter pins is L1, L2 and L3
(previously designated respectively R, S and T). Pin sizes are listed
in the table below. {FSE} |
| 2 | Comparison of 16A
plugs with and without Neutral contact. Although plug and pin sizes are
largely identical, a 4-pin plug does not fit in a 5-pin socket, because
4-pin plugs have two grooves and 5-pin plugs have 3 grooves. Sockets
have corresponding ridges (see image 4). |
| 3 | 16A - 380V
three-phase plug with Neutral contact. Model no. 3632-40*. The red
arrow probably points to the Neutral contact (see image 5). Pin sizes
are listed in the table below.
{FSE} |
| * | Plug
nos 1 and 3 have the characteristic triangular logo used by the Czech
company Elektro-Praga. Plugs have been donated by Spezialelectric in
Ludwigsburg, Germany. A note was added to plug no. 1, stating that the
plug was bought from SEZ (Slovenské
Elektrotechnické Závody) in Dolný Kubín, Slovakia; a company that
once belonged to the
state-owned group of electro-technical companies managed by
Elektro-Praga. In 1970 SEZ separated from Elektro-Praga, but the SEZ
logo still carries the triangular logo. |
| Examples of
flat pin plugs made by companies in other countries |
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| 4 | 25A - 380V 3-phase +
earth, 4-pin plug and matching socket, made by the Polish company Ospel. Overall size of the 25A plug and pins are approximately 15% larger than the 16A model shown in image no. 1. |
| 5 | 15A - 380V 3-phase +
N + earth, 5-pin plug, made by the Dutch company Hazemeyer in Hengelo
(HH). Plug and pin sizes are essentially identical to the 16A model shown in image no. 3. |
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Pin sizes of Elektro-Praga / SEZ 16A
3-phase plugs shown in image nos 1 (4-pin) and 3 (5-pin). a: length
b: width c: thickness d: pin spacing |
| 4-pin plug (3632-20) |
5-pin plug (3632-40) |
| sizes in mm |
L pins |
earth pin |
L pins | N pin | earth pin | |
| length (a) |
22.4 |
25.4 |
21.8 |
24.6 |
25.0 |
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| width (b) |
7.9 |
7.9 |
7.9 |
7.9 |
7.9 |
|
| thickness (c) |
2.6 |
2.6 |
2.6 |
2.6 |
2.6 |
| pin spacing |
13.0 / 26.0 / 13.0 |
13.0 / 13.0 /
13.0 / 13.0 |
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D i g i t a l M u s e u m o f |  |
P l u g s a n d S o c k e t s | |