I continue to test extension cords. Today I will study not the cheapest extension cord of the Russian brand Start with a declared maximum load power of 2200 W, a switch, grounding, five sockets and a three-meter cable.
Extension C / U S 5x3-ZV can now be found at a price of 320 rubles. It is sold in a transparent color-printed bag.
The package indicates a maximum load of 2200 W, the promised wire is 100% copper, non-flammable housing, compliance with standards.
The body of the extension cord is collapsible, but it is unlikely to be disassembled: self-tapping screws with a very non-standard head are used (three cutouts along the edges).
To disassemble the extension cord, I had to drill out the attachment points.
Everything inside is done very carefully. Good soldering, the cable is fixed with a plate with two self-tapping screws. A switch equipped with an indicator breaks both wires.
The wires are crimped and then welded to the contact plates. The plates are made of metal, 0.5 mm thick (I have met 0.23 mm in cheap extension cords). Blue plastic inserts exclude pushing the ground bar and shorting to the phase and zero bars, which sometimes happens with cheap extension cords.
I checked, the plastic of both parts of the case really does not burn.
The following parameters are indicated on the package:
Rated voltage: 250V / 50Hz
Maximum load 2200 W / 10A
Flame retardant plastic housing
100% copper wire
Wire cross section 3x0.75 mm².
On the plug and the body of the socket strip there is a designation 10/250, in addition, on the bottom of the body there is an inscription “Max. 2200 W ".
The wire has the inscription "3G0.75mm²".
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 88 cm. It is customary to measure the length of extension cords together with the block of outlets, in this case, 3 meters is obtained from the plug to the middle outlet.
The resistance of the signal lines of the extension cord (from the contact of the plug to the contact of another plug inserted into the extension cord) - 84 mΩ on one line and 90 mΩ on the second (near socket) and 86 mΩ on one line and 91 mΩ on the second (far socket). The resistance of the ground line is 81 mΩ to the nearest socket and 84 mΩ to the far one.
The wires consist of 24 wires with a diameter of 0.19 mm, which corresponds to a total cross-section of ~ 0.68 mm².
The resistance of the cores in a 2 m 80 cm section of the wire was 70 mOhm (25 Ohm / km). This resistance corresponds to a copper conductor cross-section of 0.69 mm².
By GOST 22483-2012 (Table 5) the resistance of a kilometer of wire core 0.75 mm² should be no more than 25.5 Ohm, so that the wire with a small margin fits into the requirements of GOST for a cross-section of 0.75 mm².
To test the operation at maximum load, electric heaters with a total power of 2280 W were connected to the extension cord.
Mains voltage 226 V. Current 10.07A. Indoor temperature 26 ° C.
After 30 minutes, the maximum temperature of the outer sheath of the wire was 38 ° C.
The temperature in the plug and the body of the socket strip is not very hot.
The extension cord copes with the stated load with a good margin.
Great extension cord. Everything is done neatly and "according to the mind", including what is not visible from the outside (for example, protective pads that prevent the earthen tire from being pushed through). This is just the case when it is better to buy a thing a little more expensive, but of really good quality.
© 2020, 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.