Museum of Plugs and Sockets logo, small South Africa (part 2)
1920-1990s plugs and sockets
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1900
-1920
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2000-...
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Pin sizes of BS 372 Part I (2-pin) and BS 546 (3-pin) 15A and 5A plugs are given below.
Each of the plug, sockets and adapters shown below has been donated by Peter Coates {PC}.

 

Plugs and sockets without earth connection, conform to BS 372 Part I:1930

Goltone 15A 2 pin socket Goltone- 5A 2-pin socket GEC 15A 2-pin plug GEC 15A 2-pin plug

Goltone 5A 2-pin socket
Litemaster 5A 2-pin plug
MK 5A 2-pin socket
MK 5A 2-pin socket

1, 2
BS 372 Part I, 15A-250V socket. Both socket nos. 1 and 5 have tubular socket contacts with laterally projecting binding screws for securing wires (image no. 2). Patent applicants were Ward Goldstone Ltd and Sampson Goldstone; patent 473440 was published October 13, 1937. Ward and Goldstone used the brand name Goltone. In 1984 the company was renamed as Volex.
Socket no. 1 has a circular groove with a diameter equal to spacing between contact holes. The groove facilitates the insertion of a plug.    {PC}
3, 4
BS 372 Part I, 15A-250V plug. The characteristic logo, redrawn bottom left indicates the origin of the plug: General Electric Company, England. The plug dates back to the late 1920s or early 1930s.   {PC}
5
BS 372 Part I, 5A-250V socket. Brand name: Goltone (Ward & Goldstone Ltd), Manchester. See caption of image no. 2 for further details.   {PC}
6 Bakelite 5A, 2-pole plug made by Litemaster, South Africa in the 1950s. Note that the flex cable entry is opposite the plug face. Although it was a very common type of plug in both the UK and South Africa, they do not fully comply with BS 372 Part I. The British Standard requires that the cord enters at the side (note given by David Peacock).   {PC}
7, 8 Switched 5A-250V socket, made by MK Electric, England; probably late 1930s. See caption of image no. 15 for details about the patented inextensible band around each of the contacts.   {PC}

  

Plugs and sockets with earth connection, conform to BS 317: 1928,  BS 372 Part II:1930  or  BS 546:1934

Temco 5A 3-pin outlet Temco 5A 3-pin outlet Temco 5A 3-pin outlet
Temco logo

MK 5A 3-pin outlet MK 5A 3-pin outlet
MK 5A 3-pin outlet
MK Electric logo, older version

9 - 12
Porcelain, switched, 5A-250V socket. Probably conform BS 317, but not stated. The top cover is made of Bakelite. The rather delicate socket dates back to the 1930s. Brand name: Temco (see no. 12). Temco was a brand of the Telephone Manufacturing Company, London (TMC). The electrical accessories branch, was sold in the early 1950s to Ward & Goldstone. Later some items were branded as Volex Temco.   {PC}
Information about the English companies Goltone and Temco has been  provided by David Peacock.
13 - 16
MK Electric 5A-250V, BSS 546 socket (BSS = British Standards Specification, later abbreviated to BS). Porcelain body, Bakelite cover. Images 14 and 15 show that the early 1930s model already was provided with safely shutters. The earth pin opens the shutters. To illustrate the principle a detached earth pin of an older model Litemaster plug has been (mis)used; see image no. 18.
Another interesting feature are resilient socket contacts (see no. 15). Contacts, that have a bell mouth, are surrounded by an inextensible band (green arrow). A spring (blue arrow) is employed to increase the resilience of the contact and assists in positioning the band. This improvement has been patented in 1933 by Charles L. Arnold and MK Electric Ltd. Patent no. 402474.
   {PC}

 

BS 546 based 3- pin 15A and 5A plugs (corresponding to SANS 164-1 and -3)

Litemaster 15A 3-pin plugs Litemaster 15A 3-pin plugs

Litemaster 15A 3-pin plug, top view Litemaster 5A 3-pin plugs Litemaster logo, old model

17 - 20
BS 546 15A-250V (nos. 17-19) and 5A-250V (no. 20) plugs made in South Africa by Litemaster. For both 15A and 5A an 'older' and a 'newer' model is shown. Older and newer is defined by the way the country of origin is indicated. Older plugs are Made in South Africa (or S.A.), whereas newer plugs are made in R.S.A. (Republic of South Africa). South Africa became a republic on 31 May 1961. With respect to Litemaster BS 546 plugs it is assumed that 'older' means 1950s - early 1961, and 'newer' corresponds to late 1961 until mid 1990s, when the SABS mark of approval was introduced and R.S.A. gradually disappeared.   {PC}

Older BS 546 15A and 5A plugs had three noticeable
differences in comparison to newer plugs.
1.
Older plugs have an inspection hole to check earth pin wiring. Newer plug don't have a hole (see image 17).
2.
Older pins are partially split; newer pins are solid. Partially split pins gave flexibility that was needed when plugged into sockets equipped with inflexible hollow contact tubes.
3.
Older plugs have pins that are screwed onto the cord grips through the Bakelite base (see image 18, left). It was a potentially unsafe construction because
pins easily came undone.
Newer plugs had pins that could be taken out from the inside of the plug to connect wires (see image 18, right). A square metal plate prevented them turning and the plug cover held the pin in place.

Note that the shape of older and newer 15A plugs has changed little, but the shape of 5A plugs has been adapted.

 

Adapter plugs

Litemaster 3-way adapter plug Litemaster 3-way adapter plug, detail
Litemaster 3-way adapter plug, with 5A and 15A plugs
 

Litemaster 5A 2-way adapter plug Procast 15A 2-way adapter plug
Procast logo
 
Easy-Pull strap

21 - 23
Litemaster 15A 3-way multi-plug with one 15A outlet and two 5A outlets. The 5A outlets can be used for 3-pin and 2-pin plugs, because the holes for power pins are oval (see no. 22) and the N and L contacts have some flexibility. The difference in N-L pin spacing between 2-pin and 3-pin plugs is only 2.1 mm. Pin diameter  and pin length are identical. Image no.23 shows the use of both types of 5A plugs. Multi-plug has been made in R.S.A. and dates back to the 1978s or '80s.   {PC}
24 Litemaster 5A 2-way multi-plug with two outlets for 3-pin 5A plugs. Multi-plug has partly split pins and is made in S.A.; probably late 1950s.   {PC}
25, 26
15A 3-way multi-plug with two 15A  3-pin outlets. Made by Procast Manufacturing (Pty) Ltd, Maitland, Western Cape, South Africa in the 1980s-'90s.   {PC}
27 Strap that may look as suspenders, but is a helpful tool to release a plug. See Easy-Pull page for details.

 

Characteristics of
classic South African
plugs displayed above

BS546 15A plug, small
BS5372(1) 15A plug, small
BS546 5A plug, small
BS373(1) 5A plug, small

15 A, 3-pin
BS 546
15 A, 2-pin
BS
372 Part I
5 A, 3-pin
BS 546
5 A, 2-pin  (see caption to image 6)
Diameter of L and N pins 7.1 mm 7.1 mm 5.1 mm 5.1 mm
Length of L and N pins 20.2 mm 21.0 mm
15.7 mm 15.5 mm
Spacing of L and N pins 25.2 mm 22.1 mm  18.8 mm 16.7 mm
Diameter of earth pin
8.6 mm n.a. 7.1 mm n.a.
Length of earth pin 28.5 mm n.a.
20.3 mm
n.a.
Offset of earth pin 25.6 mm n.a.
20.1 mm
n.a.
Note: pins of classic plugs are not always firmly fixed; length, spacing and offset may vary +/- 0.5 mm. L-N pin spacing and earth pin offset are measured between pin centers.

 


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-1920
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