Source: https://www.irem.it/en/protection-against-mains-power-faults/integrated-power-supplies/serie-ai/
Timestamp: 2018-09-23 13:03:06
Document Index: 468415485

Matched Legal Cases: ['art 4', 'Art. 412', 'Art. 412', 'Art. 412', 'Art. 413', 'Art. 413', 'Art. 413']

SERIE AI - Integrated power supplies - IREM | Power - Hydro- Lighting
to assure the safety of operators working on the plants, ac-cor-ding to the law;
to assure continuity of ope-ra-tion to the plants;
to build a compact di-stri-bu-tion system for all loads usually present in relay stations;
to limit the costs of in-stal-la-tion and management;
to allow a cheap and ef-fec-tive technical assistance.
The primary consideration has always been the safety of operators working on the equipment, as established in EEC directives 89/391/Eg, 89/654/Eg, 89/656/Eg, 90/269/Eg, 90/270/ Eg, 90/394/ Eg, 90/679/Eg “on the improvement of the safety and health of workers in the work place”.
The problem can be solved by producing professionally made equipment and by simply applying the International Standards HD 384/4/41, IEC 364-4-41 “Electrical installations of buildings – Part 4: Protection for safety – Chapter 41: Protection against electric shock”.
This regulation describes protective measures intended to ensure the safety from electric shock in normal service and in case of fault. It also includes particular requirements applicable to TN, TT and IT system earthing. It is considered a basic safety publication.
Chapter 41 “Protection against electric shock”
Art. 412 “Protection against electric shock in normal service (protectionagainst direct contact or basic protection)
Art. 412.1 Protection by insulation of live parts
Art. 412.2 Protection by barriers or enclosures
Art. 413 “Protection against electric shock in case of fault” (protection against indirect contact)
Art. 413.1.1.1 Protection by automatic disconnection of supply
Art. 413.5 Protection by electrical separation
Remark: for voltage bands for electrical installations of buildings, see IEC 449. It has the status of a basic safety publication in accordance with IEC Guide 104.
a. a spark-gap magnetic blow-out lightning arrester. This is an essential component of the integrated power supply. It is characterized by:
restoration of the plant normal operating conditions in-ter-rup-ting the arc current at its first passage through 0 after the exhaus-tion of the overvoltage wave;
capability of withstanding currents with peak value of 100 kA (10/350 µs), charge of 80 As and specific energy of 1,25 MJ/Ω;
auto-regenerability. Thanks to this characteristic, the arrester does not need to be replaced, as it happens with other over vol-ta-ge protec-tion systems.
b. An input circuit breaker, providing protection against short circuits and acting as main circuit breaker. It has a high ma-gne-tic tripping characteristic, avoiding untimely openings following im-pulse type overcurrents caused by atmospheric discharges.
c. A single-phase isolation transformer compliant with EN60742 Standard, provided with electrostatic shield between the windings. In addition to the galvanic isolation of the users from the line, it also ensures good attenuation against common and transverse mode conducted noise. On the secondary of the isolation transformer there are four lines, each one protected by a suitably rated circuit breaker, used for the power supply of a receiver (RX), a transmitter (TX), auxiliary equipment (e.g. air conditioner) and users (welder, drill). There is a multi-standard socket on each output. The breakers are fixed on a fiberglass support with high mechanical resistance in order to assure an adequate isolation from the metal frame.
d. A device signalling breakdown of insulation with relevant contact wired to the terminal board. This device intervenes when the insulation is lower than 100kΩ.tramite contatto riportato a morsettiera. Esso interviene quando l’isolamento è inferiore a 100 kΩ.