Features of an electrical supply of devices

Features of an electrical supply of devices

The Requirements shown to an electrical supply of devices of automatics and telemechanics . For accurate work of devices of automatics and railway transportation telemechanics the reliable and continuous electrical supply is necessary. Devices STSB of a railway transportation and other consumers entering into their complex concern various groups of electroreceivers.

Devices of electric centralisation of divisionals concern consumers of special group of I category, central passenger and switchyards with number of arrows more than 30, and also the central posts of centralised traffic control.

Consumers of I category are devices: electric centralisation of intermediate stations with number of arrows to 30; automatic lock-outs, the sorting mechanised hills; светофорной alarm systems with key dependence; tunnel and переездной alarm systems; technological loading of posts of detection of an overheat of axle boxes (ПОНАБ); control points AJIC; points of writing off of numbers of cars in switchyards with an automatic control system; external illumination of tops of hills, ways надвига and zones замедлителей; the landslide alarm system.

Consumers of I category concern also guaranteed (minimum necessary) illumination in the buildings, providing operation of devices STSB, ventilation of power station and accumulator rooms.

To consumers of II category belong: compressor stations for pneumatic clearing of arrows of electric centralisation; pressure-blowing stations of pneumatic mails and points of writing off of numbers of cars in the switchyards which do not have an automatic control system; external illumination of car yards of the mechanised hills (except for a zone замедлителей which concern I category).

Consumers of III category are: internal illumination and the general ventilation of all sluzhebno-technical buildings, devices STSB and the mechanised hump yards; kontrolno-test points of devices and equipment СЦБ; workshops, монтерские points, network areas, garages.

Joining of devices STSB to power supplies. The electroreceivers which infringement of an electrical supply can lead to danger to life of people, a considerable damage to a national economy, equipment damage, mass marriage of production, frustration of difficult technological process, infringement of especially important elements of municipal economy concern consumers of I category. Therefore the specified consumers should receive a food from reliable, constantly operating power supply systems, power stations, substations or the transmission lines having sufficient capacity both having stable frequency and pressure on the tyres.

The place of joining of lines is meant concept of "the tyre of power supplies» low or a high voltage, feeding devices STSB, is direct or through lowering and dividing transformers.

Receivers of I category should be provided with the electric power from two independent power supplies and the break of their electrical supply can be admitted only for the period of automatic input of a reserve food. This time should be minimum, but no more than 1,3 with.

For special group of receivers of I category it is necessary to provide an additional electrical supply from the third independent source. As such source use the automated diesel engines-generators or storage batteries.

Receivers concern consumers of II category, having rummaged in which electrical supply is connected with mass недоотпуском production, idle time of workers, mechanisms and industrial transport, infringement of normal labour activity of a great number of city dwellers.

It is necessary to provide receivers of II category with the electric power from two independent power supplies, a food on one air or cable line is supposed. The cable line or cable inserts in an air-line should be executed two cables, each of which choose on is long to a line safe load. At infringement of an electrical supply from one of power supplies or damage of an air or cable line electrical supply breaks for time necessary for inclusion of a reserve food or elimination of damage by actions of the personnel on duty or an exit brigade are admissible.

For an electrical supply of consumers I and II categories energy sources should be substations or the transmission lines entering into a power supply system, or power stations which should have not less than two units, each of which on capacity can provide all electric active and jet loadings from devices STSB and other receivers working with them in a complex.

At absence for a food of devices STSB of two independent sources from which a food of receivers I is carried out and II categories, uninterrupted operation of a food of devices is provided a diesel engine-generating with installation, and at rather small capacities — is direct from storage batteries or through converters.

For reservation of a food by an alternating current establish the automated diesel engines-generators of the second degree of automation by capacity 16, 24 and 48 kw or power stations capacity of 8 kw.

All loadings of devices STSB and the mechanised hump yards should be connected to power supplies by separate feeding lines. For devices of automatic lock-out, dispatching and electric centralisation on entrance clips of cable boxes of alarm installations and tyres of introduction panels of posts ЭЦ and ДЦ the norm of phase pressure should be 230 In at frequency of 50 Hz ± 2 %. The deviation from the established norms of pressure is supposed towards reduction no more than 10 %, and towards increase no more than 5 %.

That these requirements were fulfilled, the area of cross-section section of wires and cables of feeding lines select special calculation, provide the equipment разъединителей high-voltage line СЦБ devices of remote control from premise ДСП, and automatic lock-out feeders — devices of automatic repeated inclusion (АПВ), automatic inclusion of a reserve (АВР), control of single-phase grounding and remote control of feeding switches, and also the alarm system of action of these devices. Relay protection and automatics of feeding points of high-voltage lines СЦБ should provide pressure restoration on a line no more than for 1,3 with the ambassador of occurrence of short circuit.

The basic requirements shown to secondary sources of power supplies. Secondary sources of power supplies of devices of automatics are intended for a charge of acid storage batteries from a network of an alternating current and transformation of a direct current of batteries in variable at deenergizing of the basic power supplies.

One of the basic requirements shown to secondary sources of power supplies, maintenance of high reliability of power supply systems is. Essential increase of reliability and equipment is reached at the expense of replacement of machine converters on static in which is not present быстроизнашиваемых details and there is no increase in starting currents.

The important requirement to modern equipment of power supplies is the maximum reduction of working costs. Expenses of time of attendants for service of devices concern them, manufacture of preventive measurements and survey, and also on check and operating repair on repair-those-nologicheskih sites.

Expenses of time for check and repair of equipment of power supplies thanks to application of more reliable semi-conductor devices which have no difficult mechanical adjustments and which periodicity of checks is much more rare, than relay devices are reduced.

At creation of schemes of power supplies aspire to reduction of capital expenses for equipment manufacturing. For example, in one design with repeated use almost all making details are combined the direct current converter in variable and the charger which work неодновременно.

The important requirement is the economy of the electric power. Reduction of the expense of the electric power gives the chance to apply accumulators of smaller capacity, i.e. to save scarce materials. The economy of the electric power is reached first of all at the expense of increase to. The item д. Secondary power supplies and use of more favourable mode of a charge of batteries.