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Breakers.
Vending machines are designed to protect against short circuit and overload protection of electric lines and receivers of energy for on and off line and receivers of energy. Circuit breaker consists of the following:
- Contact system.
- The mechanism of a free trip.
- Tripping (the electromagnetic and thermal).
- Arc chutes.
Contact the system is designed specifically for switching electrical circuits.
The mechanism of a free trip allows you to switch automatically or "manually".
The releases provide a circuit breaker for overload and short circuit (thermal and magnetic, respectively). The work of the heat release is based on the thermal effect of the current: when a current above the nominal temperature bimetallic plate, due to the difference of thermal expansion of metals of which it consists, bends and affects the mechanism of a free trip. Electromagnetic release acts like a relay with an anchor: the flow of short-circuit current anchor set in motion by the electromagnetic field acts on all the same mechanism of a free trip.
Modern circuit breakers BA series are of two types of protection: thermal (bimetallic made on the plate), designed to protect against long-term current overload and dynamic (it is performed on the electromagnetic electromagnetic coil) designed to protect against short circuit currents. Contact the system consists of fixed contacts mounted on the housing and movable contacts, hinge planted on the half lever control mechanism, and provides, as a rule, a single open circuit. Interrupter device is installed at each pole breaker, and is intended for the localization of the electric arc to a limited extent.
These older machines like AP50 have the same types of protection, but done in a much larger form factor. Modern technology can certainly do circuit breakers are much smaller (with the same nominal current). In the home use machines BA in combination with modern shields is recommended. Well, in severe conditions with frequent reconnecting cables, overloading the application of automata AP50 and others like him are still reasonable.
We are primarily interested in domestic electrical installations so a closer look at automatic VA. Combined clips from silver-plated copper and galvanized steel provide good contact with the copper and aluminum conductors cross-section from 1 to 25 square meters. mm.
BA switches are redesigned control mechanism and the mechanism of a free trip to reduce the effect of contact rattly, so that, while turning, contact closure occurs instantaneously regardless of the speed control knob. Installed a metal plate on the side wall in the NC contacts prevents the body from burning. In the manufacture of the body using high quality non-combustible materials with high heat-resistant, shockproof performance and have high mechanical strength. When assembling the first of multiple switches, each pole clinch separately, after which the poles are joined together. Terminals, are deeply immersed into the shell, provide a high degree of safety with a random person to touch the unit. Bimetallic plate is connected to the mechanism of a free trip without backlash, which improves the sensitivity of the device at its bend. Switches are available in one-, two-, three-and four versions:
One-and two-pole circuit breakers are of general application for protection of power, lighting and other installations. They are designed for manual switching and automatic or manual disconnection of electric consumers under load. Circuit breakers are used bipolar performance, usually in DC and 63 A mounting block, rail or panel. Three-pole (three phase) circuit breakers are of general application for protection of power, lighting and other installations, as well as motors from the emergency operation, short circuit, overcurrent and undervoltage. They are designed for manual switching and automatic or manual disconnection of electric consumers under load. Three-pole circuit-breakers are used in the performance of AC circuits with three-phase load (for example, asynchronous motor with squirrel cage). The releases can be built in one, two or three poles depending on the performance of the machine. Four-breakers are of general application for protection of power, lighting and other installations, as well as motors from the emergency operation, short circuit and overcurrent. They are designed for manual switching and automatic or manual disconnection of electric consumers under load. Four-pole circuit-breakers are used in the performance of AC circuits with three-phase load (for example, asynchronous motor with squirrel cage). The releases can be built in one, two or three poles depending on the performance of the machine.
Proper operation of the switch time of 0.02 seconds. Operating conditions: ambient temperature shall be between -5 to +40 ° C, and its daily average must not exceed +35 ° C. The switch is mounted on DIN rail 35 x 7.5 mm. Operating position vertical switches, the designation of "OFF" position down. Before installing the switch machine to check for signs of damage, and make a few on and off, make sure that the mechanism is working properly. Check the label on the machine, whether it meets the requirements. To connect you must use copper conductors (cables) or copper connecting bus. Supply voltage to the outputs of the switch from the power source is carried out by the findings of 1,3,5,7, ie the top. For mounting in switchboards old-style, to replace the AU to BA, provided the plastic adapter.
Selected circuit breakers rated current, voltage, and operating conditions (based on the type of performance). If you need to choose a machine to connect the known loads to calculate the current.
The value of the rated current Ip, A, is defined by the formulas:
a) for single-phase networks
Ip = Pp / (Un * cosf)
b) for three-phase networks
Ip = Pp / (1,73 * Un * cosf)
where: Pp - estimated capacity factor is determined by taking into account the demand of Kc (from reference books).
Kc = Pp / Rust
where: Un - Nominal voltage, V; cos p - power factor. Characterizes the nature of the load (active or reactive) for incandescent lamps and heaters cos p = 1. For motors in the passport indicates nominal power to the motor shaft. The motor power of the network will be:
Rpotr = Ph / n
Where: Ph - nominal motor power, kW; n - Efficiency; Rpotr - power consumption of the network, kW. Based on the obtained values of the current circuit breaker is selected. Of course the automaton has a lot of important parameters, but in everyday life can make your choice based on compliance with the nominal current and voltage and load connected.
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