C9 IEC The IEC C9 is listed under IEC 60320, and is rated 6A at 250V and 70°C; it is class II, so ungrounded. The corresponding appliance inlet is the C10. Historically a polarised version, the C11 connector and C12 inlet, also existed, but this has been withdrawn from the IEC standard. Being unearthed, the C9 is not permitted for sale as a rewireable connector; once wired onto cable it cannot be disassembled.
Largely phased out in the 1980s in favour of more standard IEC connectors, the C9 is mostly used on audio equipment, including synthesisers, reel-to-reel tape machines, hifis, turntables etc. Another use is in sewing machines and knitting machines. Manufacturers known to have used the C9 are Akai, Marantz, Revox, Roland, Singer, Tandberg, and Telefunken.
We offer the C9 both as a loose wireable connector, and assembled onto a variety of international mains cables, where the most common is a UK plug to C9 IEC on 2 metres of cable.
HNA plug The HNA plug was specified by the HNA (Handelsschiff Normen Ausschuss or Merchant Shipping Standards Committee) in the 1920s-30s; the committee later became part of the DIN (Deutsches Institüt für Normung).
The original HNA specification is rated 10A 250V with round pins, and has a waterproof design for maritime use. A later version for domestic use has flat pins (4.8 x 2.5mm) and isn’t waterproof; this is the type we supply as a rewireable plug, or alternatively assembled, usually as an HNA plug to C13 IEC. The HNA plug is usually used on specific applications, for example data circuits.
Electrak key plug The Electrak key plug has three brass pins mounted on a barrel that fits inside the socket, which is inserted and then turned 90 degrees like a key.
The Electrak key socket is shuttered to prevent access when no plug is engaged.
The locking mechanism stops unauthorised or accidental removal, and the non-standard design prevents use of normal mains plugs (although an adaptor does exist). There are three different types manufactured by Electrak:
The three versions have a plastic leader in front of different pins, which makes the three types not interchangeable. The Electrak plug is rated at 240V 13A, and is fitted with a standard BS1362 fuse; this is normally 13A, but can be changed to a lower rated fuse.
The DIN 49491 connectors (originally DIN 4990, DIN 4991) were predecessors of the current IEC 60320 range, used in a variety of domestic appliances from the 1920s to the 1960s. The German names Waffeleisenstecker (waffle iron plug), Bügeleisenstecker (electric iron plug), and Heißgerätekabel (hot equipment cable) give an idea of the typical uses, which also included kettles, electric urns and slide projectors. Comparing DIN 49491 to IEC 60320 shows a few safety improvements that have been made.
Not all connectors are earthed, but the appliance inlet accepts both earthed and unearthed versions; the earth is the steel clip on the face of the connector. The insulator is made from porcelain, and the main body from Bakelite: this could conduct heat from the device to the connector body and a potential burn risk to the user when unplugging the connector. The apertures for the line and neutral are large enough to pose a shock hazard from small metal objects or children’s fingers. Porcelain and Bakelite are also both brittle materials and prone to breaking when dropped.
For these reasons DIN49491 is no longer on the open market as electrical connectors. Current industrial specialist applications include powering injection moulding machines and extruders, heated thermoset moulds and solder baths etc.
Morvan Trading Ltd has over 40 years experience in the powercord business.
We are a family business established in 1991 who pride ourselves on our knowledge of cord sets and commitment to customer service.