Determination of electrotechnical products.
All electrotechnical products must meet the basic functional and operational conditions, and above all, guarantee the safety of the user. In addition, they must be characterized by reliability of operation, sufficient durability, easy to install and use, as well as have the desired aesthetic qualities. To ensure safety, special protective measures are additionally introduced into electrical installations and equipment, which are intended to prevent an electric shock or limit the temporary flow of current by turning off the power.
Zeroing is one of the means used in devices with a voltage not exceeding 500 V. All conductive parts of the device are directly connected to the grounded protective conductor.
Grounding allows conductive parts to be connected to ground buried in the ground, which automatically disconnects the power supply during interference.
Fuses and circuit breakers are also used as protection.
In order to determine, to what extent the finished electrotechnical products meet the requirements of the standards, a lot of specialized research is carried out, the effect of which is most often the manufacturer's assurance of the appropriate level of quality and the possibility of marking his products with the QC quality control mark and the "B" safety mark.
During the quality acceptance, the seller should check:
- that the product has not been mechanically damaged during transport,
- or parts (visible) conductive are well protected,
- or plugins, knobs, the door works well,
- whether the products are well labeled,
- the condition of the packaging.
Packaging of electrotechnical products is very different, adapted to the properties, usage, and also to the construction of the product itself. Most often, it is used for the production of packaging: paper materials - wrapping paper, semi-rigid cardboard boxes; wooden - cages, chests, spools; plastics - foils, fittings.
Markings of electrotechnical products should contain information in the form of words, letter symbols, numbers or other different combinations. They must be made permanently, readable and should apply:
- product name,
- trademark,
- rated values,
- current type designation (fixed or floating),
- rated frequency, if greater than 60 Hz,
- standard number (PN),
- safety sign,
- other information, specified in the relevant normative acts, for example. battery storage period, bulb cap type, polarity, date of production.
Some products are marked in accordance with the standard, i.e.. they bear trademarks, for example. on the bulb bulb is placed: 40 In, 220-230 V, POLAM-CONTACT, "B". In electrical engineering, you can meet with the marking of products using colors, because it is easy to distinguish them from the color of the housing, for example. for cables and wires, greenish-yellow always means protective conductors. Other veins have colors according to PN-E-90100:1996.
Examples of markings on packaging:
1) FABRYKA KABLI "OŻARÓW" S.A.. — trademark
TYPE DMY 300 V 2×1,5 mm² - Housing Cable (M), two-wire with copper conductor (D) about polyvinyl insulation (AND), Voltage 300 V
1997.06.03 — date of manufacture
KJ - Quality Control Mark
B — safety mark
2) screw-in circuit breaker — product name
FACTORY OF ELECTROTECHNICAL EQUIPMENT "KONTAKT" S.A.. CZECHOWICE-DZIEDZICE — trademark
1997 — date of manufacture
220-230/380 V, 1 A - Ratings
B — safety mark
When selling, the seller should check, whether the electrotechnical device is provided with a warranty card and an instruction manual. It is a set of information necessary for the user about the product offered by the manufacturer. Often in the manual there are basic technical data and operating conditions.