I tested an inexpensive extension cord made in Russia and found out what its potential danger is.
The Era UX-3-3m extension cord has a wire length of three meters, it has three sockets, there is no grounding.
The following parameters are indicated on the extension body:
Rated voltage: 250V;
Maximum current: 6A;
Maximum power: 1300 W.
The packaging says:
100% copper conductors, up to 1 mm²;
Flame retardant plastic housing;
GOST R 51322.1-2011.
In Russia, there is no GOST for household extension cords. The given GOST R 51322.1-2011 "Electrical plug connectors for household and similar purposes" standardizes only the parameters of the extension cord parts - plugs and sockets.
The actual length of the wire (from the point of exit from the plug to the point of entry into the socket strip) is 2 meters 87 cm, but if measured from the contacts of the plug to the end of the socket strip, it will be more than 3 meters.
The resistance of the extension cord (from the contact of the plug to the contact of another plug inserted into the extension cord) is 138 mΩ in one line and 144 mΩ in the other.
A 1320 W load was connected to the extension cord.
Mains voltage 225 V. Room temperature 26 ° C.
After 40 minutes, the wire warmed up to 33 ° C.
The extension cord successfully coped with the declared load of 1300 watts.
Heating at the junction of the wires and plug is not fixed. The contacts of the plug have heated up to 38 ° C, which is due to the low quality of the outlet into which the extension plug was plugged.
No heat detected in the socket strip.
The block of outlets is collapsible, its two halves are fastened with four self-tapping screws.
The contacts of the socket group are made of metal, 0.6 mm thick.
The wires are soldered. The soldering quality is satisfactory.
Each wire consists of 13 copper wires, 0.2 mm in diameter. The total section is 0.4 mm².
The resistance of each of the two cores of a two-meter piece of wire is 88 mΩ and 89 mΩ. This corresponds to a copper conductor cross-section of 0.38 mm².
For reference, according to GOST 22483-2012 "Conductive conductors for cables, wires and cords" nominal the resistance of a stranded conductor with a cross-section of 0.5 mm² must be no more than 39.6 Ohm / kilometer or 79.2 mΩ at 2 m.
The plastic of the case burns well.
The extension cord can handle the stated 1300 W load and can withstand a slight overpower without any particular consequences. I have no complaints about the manufacturing quality of the extension cord. The extension cord uses a non-standard 0.4 mm² wire, however, apparently, this is not a violation.
The manufacturer indicates a maximum power of 1300 W and the extension cord withstands this power, but the buyer can do not pay attention to this and connect a powerful load, such as a kettle or heater, through this extension cord. The consequences can be very deplorable, and if God forbid it comes to fire, the case of the extension cord, alas, will burn, although the packaging states that the plastic does not support combustion.
However, this extension cord can be used for low-power consumers. The main thing to remember about limiting the load is 1300 W.
© 2019, Alexey Nadezhin
The main topic of my blog is technology in human life. I write reviews, share experiences, talk about all sorts of interesting things. My second project - lamptest.ru. I test LED bulbs and help figure out which ones are good and which are not so good.