electric energy meter Product function

With rapid social progress, increasing electrical equipment. But aging and the development of lagging power transmission and distribution facilities, as well as poor design and other Electric transformer‍ causes of insufficient power supply voltage is too low, the end user, and the user is often thread voltage is high, especially for electrical equipment for voltage demanding high-tech and precision equipment, not only as a time bomb. Mains system as the public grid, above all kinds of loads connected to thousands, including some of the larger inductive, capacitive, switching power supply load only get electricity from the grid, the grid itself will in turn cause impact of the deterioration of the quality of the local power grid or power grid, resulting in the mains voltage waveform distortion or frequency drift. Another unexpected natural and man-made disasters, such as earthquakes, lightning, power transmission system is open or short circuit, will endanger the normal supply of electricity, thus affecting the normal workload.

Unstable voltage will cause a fatal injury or equipment malfunction, affecting production, resulting in delivery delays, unstable, and many other quality loss. Meanwhile accelerated Inverter Power Supply‍ aging equipment, affecting life and even burned parts, so that the owners facing trouble or in need of repair in the short term we should update equipment, waste of resources; or even serious accidents, causing incalculable damage.

So use the regulator, particularly for electrical equipment voltage demanding high-tech and sophisticated equipment is essential.‍

Voltage stabilizer Regulators Technology | regulator parameters metrics

A. regulator has an input voltage range. IEC standard for the input voltage is within the range of ± 10 rating changes. Beyond the audible alarm does not automatically make the output voltage stability in the required range.

B. output voltage regulation, is the input voltage air circuit breaker‍ changes caused by the effects of changes in output when the rated load when the input voltage source voltage range according to rating tuned up and down the upper limit value, the measurement the maximum change amount of the output voltage (±). This value is smaller the better, is an important indicator to measure the performance of AC voltage regulator.

C. Load regulation: the changes in the load caused by the effects of changes in output. Changing the size of the load current, measurement of the amount of change of the output voltage (±). This value is smaller the better, but also to measure AC voltage regulator important indicator of performance.

D. The output voltage relative harmonic content (also known as the output voltage distortion), with THD is usually said that the ratio of the total harmonic content of the fundamental rms rms, when the load is rated input voltage distortion ﹑ meet benchmarks when the condition measurement output Circuit Breakers‍ (typically less than 3), the input voltage is the lowest value and the highest value ﹑ rated voltage distortion, whichever is greatest. this value is as small as possible.

E. Efficiency: P0 is the active power and the active power Pi of the input output ratio (percentage).

F. load power factor

Regulators are or KVA capacity (KVA) value indicates the load, in addition to purely resistive load, there are inductive and capacitive loads, with VA (VA) that, in addition to the active power load, there are no reactive power. This indicator reflects the ability of AC power supply with inductive and capacitive loads.

General AC power supply, load power factor cosφ 0.8, when the product is 1KVA, the output of active power (ie, the ability with resistive load) up to:. 800W If the product is represented by 1KW (cosφ still 0.8), active power output 1KW, then output power S = 1000 / 0.8 = 1250VA. Smaller value when the load power factor, showing greater ability to adapt to the power supply of the reactive load.

G. exchange regulator parameters as well as the output power of the input frequency ﹑ ﹑ ﹑ effects of random source frequency deviation (time shift) ﹑ ﹑ load input power source power factor (this value and load power factor is different, I hope the bigger the better, maximum to 1), the relative harmonic content of Electric transformer‍ the source current ﹑ audio noise other items, three-phase AC power supply, as well as three-phase output voltage unbalance degree, definitions and test methods of these pointers can refer to the relevant standard.

electric energy meter AC power supply and DC power supply

Depending on the nature of the output of the regulator, the regulator is generally divided into AC voltage regulator (AC power supply) and DC voltage regulator (DC power supply) two Air circuit breaker‍ categories. The following highlights the DC power supply, power supply for short.

According to the regulator's work status, the power supply is often divided into two categories: linear power supply and switching power supply. In addition, there is a small power use regulator.

Switching Regulator

Switching regulator using the output stage, repeated switching "on" and "off" state, and the energy storage member (capacitors and inductors) together produce an output voltage. It is adjusted by the output voltage of the sample based on feedback to adjust the switching timing to achieve. In the fixed frequency electri calmete‍ regulator by adjusting the pulse width of the switching voltage regulator switching timing, which is called the PWM control. In the gated oscillator or pulse mode regulator, the switching pulse width and frequency remains constant, however, the output of the switch "on" or "off" by the feedback control.

The switching arrangement and the energy storage member, the resulting output voltage can be greater or less than the input voltage, and a voltage regulator may be used to generate multiple output voltages. In most cases, at the same input voltage and output voltage requirements, pulse (step-down) switching regulator higher than the linear regulator power conversion efficiency. Compensation Compensation --- precision AC power supply (single-phase 0.5kVA and above, mcb circuit breaker‍ the three-phase 1.5kVA and above) have compensation transformer with 110V output.

Voltage stabilizer Vacuum AC contactor works

Vacuum contactor vacuum interrupter media as its main contacts sealed in mcb circuit breaker‍ a special vacuum arc tube. When the operating coil is energized, the armature pull, in the role of the contact spring and vacuum autistic force contact closure; when operating coil power, the reaction force of the spring force to overcome the vacuum autistic armature release, contacts open. When the contactor breaking current, the contact gap will be formed from a metal vapor to form platinum scale, affecting the life of the contactor.

AC contactor selection

AC contactor selection, Circuit Breakers‍ the selection should be reasonable and based on the type of work load parameters. Specifically divided into the following steps:

1. Select the type of contactor

AC contactor according to the type of load is generally divided into Type I, II, III and IV, respectively denoted AC1, AC2, AC3 and AC4. A corresponding class of AC contactor control object is no sense or micro sense load, such as incandescent, resistance furnace; II AC contactor for wound rotor induction motor starting and stopping; three AC contactor typical use is squirrel cage induction motor running and running carve off; four AC contactor for Electric transformer‍ squirrel cage induction motor starting, reverse brake, reverse and jog.

electric energy meter Select the contact's ratings

According to the controlled object and operating parameters such as voltage, current, power, frequency and operating system, such as determining the power transformers‍ contactor ratings.

1) contactor coil voltage, should generally be lower as well, so that contact can reduce the insulation requirements, while also safer to use. However, in order to facilitate and reduce the equipment electric energy meter‍, often by the actual grid voltage selection.

2) operation of the motor frequency is not high, such as compressors, pumps, fans, air conditioners, punch, etc., contact rated load current is greater than the rated current can be. Contactor type can be used CJl0, CJ20 and so on.

3) heavy duty motors, such as machine main motor, lifting equipment, winches, crushers, etc., the average operating frequency of more than 100 times / min, start running, jogging, forward and reverse brake, reverse braking, etc. state, the choice CJl0Z, CJl2 type of contactor. In order to ensure the electrical life, make contacts with derating. When selected, the contactor rated current greater than the motor rated current.

4) special heavy duty motor, such as printing presses, boring, etc., high operating frequency, up to 600 to 12,000 times / h, often running start, reverse brake, reverse and other state, mcb circuit breaker‍ according to the electrical contacts roughly life and starting current selection, model selection contactor CJl0Z, CJl2 so on.

5) AC circuit capacitors into the grid or the removal from the grid, the contactor closing capacitor selection should consider the impact of current. 1.5 In general, the contactor rated capacitor current can be rated current selection, model selection CJ10, CJ20 and so on.

6) When the transformer with contactor control, you should consider the size of the inrush current. AC arc welder for example, resistance welding machines, etc., generally can be 2 times the rated current of the transformer selected contact, model selection CJl0, CJ20 and so on.

7) For the electric equipment, such as a resistance furnace, electric heaters, etc., cold resistance load is small, so the starting current corresponding to a large number. May not consider (starting current) when selecting contacts, press the load rated current selection. Models can be used CJl0, CJ20, etc.

8) Because of the gas discharge lamp starting current, starting a long time, for the control of lighting equipment, according to the rated current of 1.1 to 1.4 times the selected AC contactor, models available CJl0, CJ20 and so on.

9) Contactor contactor rated current is under long-term maximum allowable current, duration ≤8h, and installed in the open control panel, if the cooling conditions are poor, the selection of contactors, the contactor rated by 110% to 120% of rated load current selection. For the motor to work long hours, due to the oxide film is no chance to get it cleared, the contact resistance increases, resulting in contact heat exceeds the allowable Air circuit breaker‍ temperature rise. When the actual selection, you can contact the rated current is reduced by 30% using.

Voltage stabilizer Operational use Eight hour working day

AC contactor which is the basic duty. Contactor Conventional thermal current parameters is determined Click duty, under normal circumstances the specifications of various series contactors are Inverter Power Supply‍ suitable for eight hour working day. Such duty contactor which closes the main contact in the case of thermal equilibrium can be achieved by the rated current, but after eight hours should be divided.

Uninterrupted work system

Such work system is a long-term work system, that is the main contacts remain closed for the duration of carrying a steady current of more than eight hours (a few weeks or even years) is not breaking current working system. Contacts in the contact oxidation and long-term accumulation of dust in working condition electric transformer‍ unchanged easy voltage stabilizer, these factors will lead to the deterioration of thermal conditions, phase to phase, relatively insulated reduce creepage phenomenon even prone to short-circuit. When the conditions required to work in this type of work contactor system, AC contactor must derating or special design, easy to gather dust should use, creepage distance between the larger models. Dusty and corrosive gas environment should pay special attention to this issue.

Short-time working

In contact with the main contact system under this type of work remain closed is not enough time to make contacts to reach thermal equilibrium, there is no load load periods separated by periods, while the load time enough to make contact with the temperature back to the initial state temperature (ie cooling medium temperature). Energy Meter‍ Short-time working contactor contacts energizing time standard value 3,10,30,60 and 90min.

electric energy meter Intermittent periodic duty

Intermittent duty cycle is repeated short-time working means contactor closing and opening times are too short to make contacts in the working system to reach thermal equilibrium. mcb circuit breaker‍ Obviously the main factors affecting the life time of such contacts is the cumulative number of operations. The main parameters describing intermittent duty cycle is powered sustained rate and operating frequency, power continued to rate the standard value of 15%, 25%, 40%, 60% of four, the operating frequency is divided into eight (1,3,12 , 120,300,600,1200) electric energy meter, each level figures mean that the number of hourly operating frequency of the contactor rated. Typically operating frequency of 100 times / h or more devices are heavy duty equipment, machine tools typical equipment (vehicles, drilling, milling, grinding), lifting equipment, mill equipment, centrifuges, coking industry, coke oven car is heavy intermittent periodic duty tasks. Operating frequency Inverter Power Supply‍ over 600 times / h belongs to special equipment heavy duty equipment, such equipment is mainly some devices similar to my company unloading port lifting equipment and machine rolling on.