On-board network aircraft is divided into:
1. Circuit direct current;
2. Circuit alternating current.
1) The DC power network is made using a single-wire system, i.e. the aircraft body is used as a negative wire, and energy from the sources is transferred to the central positive one bus No. 1, located on a special textolite panel behind the dashboard. From tires No. 1 there are main wires to the buses connecting positive terminals gas station on TSESch.
2) The AC power network consists of a single-wire, single-phase AC system, voltage 115V, frequency 400Hz and three-wire system three-phase alternating current voltage 36V, frequency 400Hz.
Energy from converters BY And PT connected to the distribution box "RK-115V,36V", installed in cargo compartment, starboard, sp.#5. It contains fuses of the type JV. And then the energy travels through the wires to consumers.
The board network includes:
1. Electrical wiring - it is made with wire BPVL(on-board wire with vinyl insulation in varnished braid) with a cross-section from 0.5 to 25 mm 2. At the center of the connection of all electrical harnesses there is a central distribution panel ( TsRShch), located on the left side, sp. No. 5,6. The negative wires are connected to the aircraft body near the consumers.
2. Protection and control equipment:
1) gas station- network protection circuit breaker ( 5-40 A);
2) JV - fuse (1-5 A);
3) IP- slow-blow fuse ( 15,50,100,150 A).
3. Mounting and installation fittings:
1) TSESch- central electrical panel - in the center dashboard;
2) Health care facilities- left control panel - on the left side;
3) CPU- central control panel.
4. Switching equipment - switches B-45, 2B-45,push switches PNG-45, buttons 205k, microswitches KV-6, relay RP, contactors KM.
5. Aircraft metallization - reliable electrical connection all metal parts of the aircraft.
Metallization provides:
1) creating a continuous negative wire;
2) potential equalization static electricity;
3) creating an effective counterweight for radio stations;
4) reduction of interference to radio reception;
5) increasing fire safety.
On-board operation When operating an aircraft's on-board network, you must
electrical network: remember that protection electrical circuits must
be carried out with fuses and automatic circuit breakers
gas station in strict accordance with the rated load currents. In the event of a failure of a unit or device, first of all you need to pay attention to the circuit protection. Bad fuse should be replaced with a serviceable one when the circuit is de-energized, setting the shutdown knob to the position "Turned off". If the circuit is protected by a machine gas station, then the fault in it is detected by the switched position of the handle.
After replacing the fuse and inspecting the device, unit (if possible), you need to re-enable the circuit by installing the switch handle or gas station to position "Enabled". Repeated fuse blown or shutdown gas station indicates a malfunction of the device, unit or circuit. In this case, you need to turn it off, report to the dispatcher and continue the flight according to the decision made.
Before the flight, you need to carefully inspect the serviceability of the electrical harnesses, the reliability and strength of their fastening on board with clamps, and the tightness of the plug connectors. On the left side in the passenger (cargo) cabin behind sp.#5 There is a set of spare fuses, electric lamps, radio tubes and semiconductor devices. When inspecting, you need to make sure that this stock is fully stocked.
Worked in normal mode, the vehicle’s on-board network must always have the nominally set voltage. Its surges can lead to possible short circuits in the electrical wiring, which will cause the failure of certain electronic devices and equipment. What should be the voltage in the car's on-board network and how to increase it - read below.
[Hide]
Normal voltage
What should be the normal voltage in the on-board network? The voltage in the vehicle's 12 V on-board network should be 14.2-14.4 Volts. This applies to all vehicles, from Zaporozhets to Gelendvagens. This parameter should be present when running engine under load.
If there is a voltage sag caused by insufficient charge battery is 12 volts, then when you turn on, for example, optics, this parameter will be below 14 volts. This is because the excitation winding of the generator device is powered from the battery through feedback. And if the battery is not fully charged, the network will not be able to provide optimal current windings and normal operation of the generator device.
This manifests itself when outdoor lighting is activated and is accompanied by total loss electrical circuit power. Lighting may be dim when driving idle speed, and when the driver gives gas, the light stabilizes to normal. Therefore, battery diagnostics should be carried out not by voltage when starting the engine, but by the electrolyte density parameter. This will prevent differences in readings between electromotive force battery and its current.
Please note that the vehicle's on-board voltage may vary depending on climatic conditions regions in which the vehicle is operated. If the car was driven from the south, and you live in the north, then a slight drop in this indicator in the car’s electrical circuit is allowed. If a vehicle is using a partially discharged battery, it must be charged, otherwise the entire charge will quickly decrease and the battery will be inoperable. If your car uses an old battery, it may begin to disintegrate over time. active mass a short circuit may occur from the plates and inside the structure. And this will cause a loss of capacity, that is, the ability to keep the battery charged.
On-board voltage vehicle should be between 14.2 and 14.4 volts with the engine turned on and energy consumers activated. Diagnosis of this indicator should be carried out at the battery terminals, and not at the terminals of the generator device.
Why does the voltage drop?
To know how to increase the voltage in the electrical circuit of a car, you need to understand the reasons:
- Battery fault- as practice shows, this is one of the common reasons. In order for the battery to replenish its charge after parking, you need to drive the car for about 20 minutes. But if the battery is discharged for certain reasons (for example, due to sulfation of the plates or due to a lack of electrolyte), then this method of replenishing the charge will not help. It is necessary to accurately identify the reason why the battery does not hold a charge and eliminate it - replenish the electrolyte level, and sometimes simply charge it. If you realize that the battery cannot be restored, then it is better to replace it.
- Generator. Incorrect operation of the generator can lead to problems with the on-board network. Before increasing the voltage in the wiring, you need to identify the cause of the malfunction of the generator unit.
- Leakage current. Sometimes it happens that a break in the electrical circuit leads to a current leak. To eliminate the problem, it is necessary to identify the exact location of the leak and eliminate the break.
- Using equipment that is not suitable. If the rating of the electrical appliances used does not match the one set by the manufacturer, this will lead to a voltage drop. If you use powerful lighting lamps or many different gadgets for which the battery is not designed, this will cause a voltage drop. The battery will provide the necessary normal operation light bulbs or electronic devices charge, but it will not have time to replenish.
How to increase?
A drop or too low on-board voltage may be due to for various reasons. Before increasing the voltage in the network from 5 to 12 Volts, you need to make sure that car generator operates normally. If the subsidence of energy is due to malfunction, then it is necessary to dismantle and repair the device, replacing the failed mechanisms with new ones.
Often this parameter falls due to a discharged battery, then perhaps it makes sense to diagnose it - check for cracks, replace the electrolyte or charge it correctly. In terms of charging, certain points must be taken into account - the procedure must be carried out using only a working charger in compliance with all rules and nuances. These points are described in detail in.
If the indicator in the electrical circuit drops, but this is not related to the operation of the generator or battery, then you can increase it on your own. The task is to “deceive” the generator regulator and make it “think” that the car’s on-board network has an even lower voltage than it actually is. Having done this, the generator device will replenish the necessary power supply; to complete this task, a diode must be added to the power circuit of the unit. In particular, it should be installed as shown in the photo.
Before you increase the voltage that is falling, keep in mind that it is important to maintain polarity when installing the diode. If the polarity is reversed, nothing will happen, but the node will not be able to provide the required charge. Note that the diode must be designed for a current of at least 5 Amps. Since the diode will heat up during operation of the generator unit, it is optimal to mount it on a radiator.
When choosing a diode element, one nuance must be taken into account - for germanium parts, the voltage drop will be about 0.3-0.7 volts, and for silicon parts - from 0.8 to 1.2 volts. This is exactly the value by which the voltage in the electrical circuit will increase. Take this point into account when choosing, it will determine final result. If the voltage in the on-board network drops to 1.2 volts, and you use a boost diode of 0.3 volts, then there will be little point in increasing the power of the on-board network.
When installing the diode element, it is necessary to ensure that the wire from it is not installed under tension; this will not be entirely convenient. The best option will increase the cable length by approximately 2 centimeters from the diode. This will make it easier to install it into the voltage relay connector of the generator device, and if dismantling is necessary, it will be easier to do.
Capacity ratio battery vehicle, generator power and power consumers - determines energy balance on-board network. The energy balance is highly dependent on the rotation speed crankshaft engine on Idling, gear ratio generator drive and vehicle operating mode.
The automobile can be compared to a reservoir from which all consumers draw electricity, which must constantly be replenished from the generator. If electricity consumption exceeds its supply, discharge battery.
A normal energy balance is when electricity consumption is equal to its supply. Mainly to disrupt the normal energy balance leads to the connection of additional electricity consumers or extreme operation of the vehicle. From the above, we can conclude that greatest influence The energy balance is affected by the operating conditions of the vehicle and the total electricity consumption.
Take, for example, high beam headlights. It is mainly used when driving a car with high speeds on country roads when the engine speed is high. In urban conditions, when the car's speed is low and the engine is running at low frequencies and idling, the high beam of the car's headlights is not used.
Such electricity consumers do not create problems due to the fact that they are mainly used for high speed engine shaft, when the car generator provides both battery charge and power to energy consumers.
In the example given, the total effect of all factors turned out to be very favorable for the energy balance of the car.
Now let's look at another example - an unfavorable one.
Included in the car fog lights, car exterior lighting and heating rear window salon This happens, for example, when there is fog. These consumers are used in cars mainly at low engine speeds. In this mode, the generator cannot deliver full power.
In this example, factors stack up unfavorably for energy balance.
Functions of the on-board network control unit
Before the advent of the on-board network control unit, all its functions were performed by several separate control units and relays. IN modern cars The on-board power supply control unit primarily monitors the electricity consumption of various consumers. With all this, it monitors the level of output voltage at the terminals battery. If the output voltage of the battery decreases to a certain value, the control unit increases the engine idle speed, which helps to increase the generator speed and, therefore, helps restore the normal state of the vehicle's on-board network.
If the on-board network control unit has a choice - the ability to start the engine or the operation of energy consumers, then the unit turns off the consumers for a while.
Typically in cars accumulator battery performs the functions of powering energy consumers and starting the engine. This means that in any situation, all electricity consumers are powered by one battery.
Over time, the number of components in a car increases, and the requirements for cold starting of the engine increase. For this reason, the reliability of power supply from a single battery was called into question. The way out is to use an additional battery in the car or use two batteries that work on a common on-board network.
additional battery
On modern campervans, some consumers (for example: refrigerator, heater, interior lighting devices, audio and video equipment, etc.) are connected to a separate network. This network is powered by its own battery.
In this case, electricity consumers do not affect the energy reserve intended to start the engine.
While the engine is running, both batteries are connected in parallel and receive charging from the generator. When the engine stops, the additional battery is disconnected from the main battery using a separating relay.
On-board network with two batteries
There are cars with a 2-battery on-board network. They have one battery intended only for starting the engine, and all other electricity consumers are connected to the second battery. Thanks to this separation of functions, even with a completely discharged mains battery, reliable engine starting is ensured.
Power automotive consumers electricity
Main consumers:
Ignition system – 20W.
Fuel injection system – 50….70W.
Fuel pump – 50….70W.
Motor control – 10W.
For cars with an extensive on-board network, when the ignition is turned on, power is consumed up to 240 W (20 A).
Long term consumers:
Fog lights - 35...55W each.
Autonomous heater – 20….60W.
Side lights – 4W each.
Audio system – 10….15W.
Backlight – 2W each.
Windshield wiper – 60….90W.
License plate lights – 5W each.
Cooling system fan – 80….600W.
Parking lights – 3….5W each.
Interior fan – 80W.
Low beam headlights – 45W each.
Headlights high beam– 55W each.
Glass heater – 120W.
Rear parking lights– 5W each.
Additional headlights – 55W each.
Short-term consumers:
Direction indicators - 21W each.
Starter – 800….3000W.
Brake signals - 21W each.
Cigarette lighter – 100W.
Lanterns reverse– 21….25W each.
Sound signal 25….100W.
Additional brake signals – 21W each.
Glow plugs – 100W each.
Headlight washer – 60W.
Electric antenna drive – 60W.
Window lifters - 150W each.
Vehicle on-board network
Sources: battery ( at start), generator.
Consumers: battery ( with the engine running), other consumers: ignition system, headlights, sidelights, alarm, fans, heated windows and seats, car audio, etc.
Voltage: 12 V and 24 V:
- 6 V - this is the on-board voltage of some cars produced before the mid-20th century. Currently, an on-board network with this voltage (6 Volts) is used only on motorcycles.
- 12 V - currently on everyone passenger cars.
- 24 V - used on heavy trucks. On light trucks, the on-board voltage can be either 12 volts or 24 volts.
In some cars and tractors, the starter operates from a 24 V network (from two batteries), and other consumers from a 12 volt network.
Motorcycle on-board network
Similar to automobile; Available in voltages: 6 V and 12 V DC.
Aircraft on-board network
Onboard electrical network aircraft is part of its electrical system and includes power transmission lines, switching and protective equipment and distribution devices. In terms of design, the BES aircraft is a complex, widely branched system of electrical communications, made taking into account numerous requirements high reliability and durability, using high quality materials and products. The manufacture of components and installation of the on-board network during the construction of a new aircraft is considered one of the most complex and expensive production operations.
Networks in an aircraft are divided into main (supply), distribution and feeder, direct and alternating current. According to the method of energy transmission - single-wire, two-wire and multi-wire - usually the “minus” of 27 volt DC networks and the “zero” of 115/208 volt networks are connected to the aircraft body.
Terminal blocks in the aircraft compartment, the left one without a cover. Wire markings are visible
Electrical wiring harnesses in the aircraft compartment, open mounting
As a rule, stranded wires made of copper or bronze stranded wires coated with tin, nickel or silver are used. Wires with conductors made of grade A-1 aluminum are used to a limited extent in high-current circuits. PVC plastic, winding made of fluoroplastic-4 film, fiberglass braids, polyamide films with a fluoroplastic coating, glass-polyamide-fluoroplastic braid made of threads coated with a fluoroplastic-4 suspension, and so on are used as insulation for aircraft wires. Wires with a cross-section from 0.2 to 90 mm2 are used - such as BPVL, BPVLA, BPDO, BPDOA, BIF, BFS, FT, BIN, BSFO, etc. All electrical wiring is assembled into bundles, bandaged and rigidly fixed using flanging clamps, in order to exclude any extraneous movements. Typically used open method installation on power elements airframe frame, but in some cases the harnesses are laid in gutters, hoses, rubber hoses (landing gear), metal pipes (on engines, inside tanks). Wrapping of harnesses with PVC or fluoroplastic tape, as well as fiberglass, self-adhesive tape LETSAR or asbestos tape is also used. In the simplest case, the bundles are simply tied in a special way with a nylon cord or a waxed thread like “makey”.
In power distribution devices, copper busbars are widely used instead of wires. In some cases it is used color coding wiring or harnesses according to system affiliation: blue - radio equipment, red - weapons, white (natural) - direct current electrical equipment, yellow or orange - alternating current electrical equipment, green - experimental systems. Phase supply wires and busbars are colored: red - phase "A", yellow - phase "B", blue - phase "C", white - neutral wire. All negative ground connections of DC networks are also colored red. In addition, without exception, all wires and harnesses in mandatory have indelible paint applied alphanumeric marking, consisting of: the serial number of the drawing of the feeder circuit - an alphabetic character, starting with the letter "A" of the Russian alphabet, digital code, corresponding to the serial number of the corresponding feeder.
The entire on-board network of the aircraft consists of large number areas joined together by various connectors and connectors: plug connectors (SHR), terminal and adapter blocks, power inputs, individual connectors, blind joints. Most widespread received plug connectors of the ShR, 2RM, 2RT, 2RMDT, SNTs, 2RMD series. In addition to connections in BES, these connectors are widely used in various on-board electronic equipment. All connectors have engraved alphanumeric markings.
To protect against electrical interference, part of the electrical wiring is shielded, braided or metal sleeves. Also, without exception, all are removable and moving blocks, units and structural elements have metallization devices (jumpers made of shielding braid).
Distribution devices are aluminum or fiberglass boxes with easily removable covers, which contain switching equipment, terminal blocks and fuses.
Very stringent requirements are imposed on the installation of BES during the production process, and on work on the BES during operation. Literally everything is standardized - the materials used, parts and tools, the order of laying each wire, bending radii, the degree of sagging of the harnesses, the distance of the harness to the airframe structure, the tightening forces of the terminals and many more parameters and quantities. And twists and tape are strictly prohibited!
see also
Notes
Literature
- BELYAKOV Andrey Leonidovich, GLADKIKH Alexander Viktorovich “POWER SOURCES FOR EQUIPMENT.”
Links
Wikimedia Foundation. 2010.
See what “On-board network” is in other dictionaries:
On-board network- A set of vehicle power wires, including the body used as a return wire Source...
- (on-board SES of the aircraft) power supply system designed to provide onboard electrical equipment aircraft with electrical energy of the required quality. A power supply system is usually called a set of devices for... ... Wikipedia
On-board local information and computing network of automatic telephone exchange- a set of electronic units (including controls) connected by high-speed channels for transmitting digital information, interacting electronic systems, designed for efficient processing and accounting of information when automating management... Dictionary-reference book of terms of normative and technical documentation
On-board local IVS of a vehicle- On-board local information and computer network ATS is a set of electronic units (including controls) of interacting electronic systems connected by high-speed digital information transmission channels, designed for efficient... ... Official terminology
Onboard equipment of the missile control system (BACS)- A set of interconnected instruments and devices that ensure the implementation of specified operating modes during combat duty, pre-launch preparation, launch and flight control of an intercontinental ballistic missile (ICBM). BASU... Encyclopedia of the Strategic Missile Forces
our side of the iron- (On-board network of the aircraft) generatordan elektrokuatyn beruge zhane ony tұtynylatyn tetikter arasynda boluge kazhetti baska kosalky equipment men қorganyshtyқ құрылғылар, мідкары currently вѓынтиғы… Kazakh explanatory terminological dictionary on military affairs
GOST 28751-90: Electrical equipment of automobiles. Electromagnetic compatibility. Conducted interference on power supply circuits. Requirements and test methods- Terminology GOST 28751 90: Electrical equipment of automobiles. Electromagnetic compatibility. Conducted interference on power supply circuits. Requirements and test methods original document: On-board network A set of vehicle power wires, including... ... Dictionary-reference book of terms of normative and technical documentation
GENERAL INFORMATION The T 64A tank is a combat tank tracked vehicle, which has powerful weapons, reliable armor protection and has high maneuverability. The tank is designed to solve a wide range of combat missions. Thanks to the powerful... ... Encyclopedia of technology
SVT 137 DRG 137 149–152/224–232 “Hamburg” DB Baureihe VT 04.5 DR Baureihe 183.0/183.2 ... Wikipedia
45-mm quad automatic deck installations SM-20-ZIF1 and ZIF-68–1- 1957 The design of the 45 mm quad deck installation SM 20 began at the MATSKB back in 1946–1947. After testing prototype machine gun SM 7 technical project The CM 20 was redesigned and introduced on October 24, 1949. According to him... Military encyclopedia
