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.

Voltage stabilizer Different requirements analysis

Different operating system of exchanges and contacts made entirely different requirements, focusing face when considering the choice of a different Switchgear & Substation‍ nature. When the "voltage stabilizer" and "short-time working" equipment selection is subject to fewer constraints contact, just consider the contactor rated operating current can be greater than the actual, proper equipment is important when you put a little margin. The ability to "stop work" system should first consider equipment selection contacts Dust-creepage prevent overheating, compact structure should not use contactor (circuit breaker for use when necessary). To prevent overheating, the contactor should enlarge the Power Supply‍ capacity of more than 20% of large chemical plant electrical equipment mostly this is the case. We must first consider the mechanical life of electrical contacts and operating mechanism of life belonging to heavy duty and special heavy task of "intermittent periodic duty" equipment selection contactors should be used CJ12 series (especially suitable for winding motor), CJ20 series or series of vacuum contactors, due to derating can greatly improve the electrical contactor life can easily be selected as the starting mcb circuit breaker‍ current of the motor contactor rated current to improve the safety and reliability of production unit.

electric energy meter Energy-saving technology

AC contactor AC contactor is widely used in low voltage circuits, is a safe, easy to control, CNC Electric‍ volume and a wide range of industrial necessities. Now commonly used in the rated current 63A and above large, medium-capacity AC contactor should more than million Taiwan dollars electric energy meter, its operating system at the time of retention of electromagnetic active power consumed between 10W ~ 100W; reactive power consumed in the Dole circuit breakers‍ spent tens to hundreds of spent between Seoul. The active power consumption distribution is roughly: 65% to 75% of the core, the short-circuit ring 25% to 30%, the coil 3% to 5%. For such a being in the industrialization and urbanization of exchanges and contacts with large country, and the energy needs of the growing tension, saving power resources has become imperative.

Such as the AC contactor solenoid operating system with an appropriate energy-saving technology to its operating system, the original design of electromagnetic ac to dc retention retention, core and short ring can save most of the loss in power, to obtain a high energy-saving efficiency (typically active saving rate> 90%). Moreover, through the Switchgear & Substation‍ transformation can reduce or eliminate noise, reduce the temperature rise of the coil and extend the service life of the contactor.

Voltage stabilizer Energy-saving products Categories

AC contactor mainly depends on its energy-saving program works and the corresponding structure processes. Fat suction within the electromagnetic AC contactor by Circuit Breakers‍ constant component F0 and F ~ alternating component composition. Among them:

Constant component: F0 = Fatm / 2 (Fatm = 107 B2 MS / 8π)

Alternating component: F ~ = F0 cos 2ωt.

At work, due to the armature reaction force always been the role of the spring, the contact springs Fr reaction force, the electromagnetic suction averages Fat> Fr; when Fat <Fr armature at the beginning of the release voltage stabilizer‍, Fat> Fr armature also was attracted state, so Again and again, the armature vibration and noise. At this point in the alternating magnetic core produced by hysteresis loss and eddy current loss will cause the core heat (superposition of silicon can play a role in reducing the eddy current losses). To reduce operating noise is usually electri calmete‍ open in the small capacity of the electromagnetic system yoke ends embedded in a small groove corresponding short-circuit ring, and its role is to be divided into two parts by the core flux, that does not pass through the magnetic flux Φ1 and short-circuit loop the magnetic flux Φ2 through the short-circuit loop, and Φ2 lag Φ1, suction is always greater than the synthesis reaction, thereby reducing the vibration and noise, but also increases the copper loss accordingly.

AC contactor power mainly by the retention power and pull the power of two parts, although larger coil pull starter instant power, but time is very short (tens of ms); working time has been in the retention hold (at this energy loss is mainly concentrated in the state of retention on iron loss). That is why if they can reduce the AC contactor work retention can save energy consumption, CNC Electric‍ according to this principle, the current energy contacts broadly categorized as follows.

Voltage stabilizer Coil-saving and Saver

Saver is divided into: capacitive, transformer, duty cycle (change) type. AC contactor Saver corresponding supporting the use of the contactor in the DC state retention operation, air circuit breaker‍ so to save energy. Saver AC contactor solenoid due to electromagnetic energy and the internal device Saver limitations generally applicable to the rated current of 60 ~ 600A AC contactor, lower than 60A AC contactor because the stored electromagnetic solenoid can run in DC maintain its pull; electromagnetic greater than 600A AC contactor can be easily generated so Saver damage internal components voltage stabilizer.

Contactor coil AC passed, it will produce a corresponding inductance, inductive influence of the size of the size of the current in the coil, AC solenoid coil inductance, the core is not closed when the inductance is small, a large current through , which is caused by the coil in the suction power of the largest timely reason. Circuit breaker‍ When the AC contactor pull into the retention time, due to long-term work in the state coupled with the coil power consumption, temperature rise. AC contactor usually work long hours can produce 50 ℃ ~ 60 ℃ degree heat, the summer plus 30 ℃ ~ 40 ℃ ambient temperature of the coil temperature rise faster. Coil long period of high temperature operation, will accelerate the aging and even burned, AC contactor life will be shortened.

According to AC contactor coil power consumption characteristics of fast rise, by reducing the power consumption and temperature to save energy. According to the internal structure, saving coil is divided into: double winding type, current limiting resistor, double winding self-conversion conversion type and location. Works will use energy-saving coil is usually on its pulsating DC coil retention program run: pull winding generally larger diameter, fewer turns, and thus lower impedance, resulting pull current large; retention winding general smaller diameter, number of turns, current transformer‍ the impedance of large, small and therefore holding current. Corresponding increase rectifiers and varistors and film capacitors, the AC contactor is energized to work in DC state, large starting current to ensure a reliable pull-electromagnetic systems, smaller holding current to reduce the retention power, thereby reducing the electrical losses and electromagnetic coil temperature of the system.

Energy-saving AC contactor

According to AC contactor structure, increasing as Power Saver, saving coil, mechanical locking device, electromagnetic system to the remanence (permanent magnet) retention type, etc., can play the energy saving effect. After contact with the tradition of saving energy, such as shown in Table 2.

Traditional CJ10, CJ12, CJ20 AC contactor, for example, for energy saving before and after comparison of the data, reflecting the energy saving effect.‍

In CJ20 / 400A / 3 year energy savings calculation: saving work properly before the contactor holding power for 180W, priced according to the average electricity tariff by 1 yuan / Kwh meter, working hours 12h / day:

Total power consumption before saving: 0.18Kw × 12h × 365 = 788 Kwh

After saving the total power consumption: 0.006Kw × 12h × 365 = 26 Kwh

Saving (annual electricity): 788Kwh - 26Kwh = 762Kwh

Cost-saving: 762Kwh × 1 元 / Kwh = 762 元

At present, energy-saving AC contactor has a certain market, but not enough popular, traditional exchanges and contacts currently in use on the dominant user. The main reason is the energy-saving type contactors expensive, the user can not accept the one-time investment, to be national policy to electric meter‍ increase efforts on the promotion of energy-saving contacts, promote the wide application of energy-efficient contactors....

electric energy meter Thyristor inverter circuit

Thyristor inverter circuit to convert the direct current into alternating current, which corresponds to a reverse process of the rectifier, is defined as an inverter. For example: power transformers‍ The thyristor electric locomotives electric energy meter, when the DC motor as a generator downhill braking operation, the locomotive of potential energy into electrical energy, trans go to the AC grid. Another example is the operation of a DC motor, brake to make it quickly, but also allows the motor as a generator to run the motor kinetic energy into electrical energy, anti-delivered to the grid. The converter operates in inverter state, if the converter is connected to the AC side of the AC power to DC to AC inverter with a Circuit breaker‍ frequency counter to the grid to go, called active inverter.

Voltage stabilizer AC inverter circuit Rationale

The DC circuit is called reverse into AC inverter circuit. In certain cases, the same set mcb circuit breaker‍ of thyristor rectifier circuit can make, but for the inverter.

The converter operates in inverter state voltage stabilizer‍, if the converter is connected to the AC side of the AC power to DC to AC inverter with a frequency counter to the grid to go, called active inverter. If the change is not the AC side current grid connection, but directly to the load, which converts DC to a certain frequency or adjustable frequency alternating current supplied to the load, then called passive inverter. AC frequency control is the use of CNC Electric‍ this principle. Except for the DC reversible active inverter speed control system, but also for AC induction motor rotor Rao line cascade control and other aspects of HVDC.

2 relative concept

Convert alternating current to direct current approach is rectified; and convert DC to AC inverter method.

Rectification, full-wave rectifying circuit is the use of one-way conduction of the diode characteristics, with four diodes connected into a bridge rectifier circuit voltage stabilizer‍, the input terminal is an AC current, the waveform is a sine wave, the direction of the alternating current, and an output terminal waveform current becomes the same direction, AC Contactors‍ and then through a filter circuit to obtain a DC waveform after filtered.

electric energy meter Inverter Classification

Source inverter also has passive inverter. For example, the DC voltage, through a simple, single-phase thyristor bridge type H, H is the output of the cross on each of the electric meter‍ four H's vertical thyristor, electric energy meter, at 34, 14 and 23 were opened to give a positive negative separated the output voltage and current.

The pulse width modulation inverter technology

Basic square wave inverter circuit is simple, but the output voltage waveform harmonic content is too large, but also both the THD (current harmonic distortion) is too large; the phase shift of multiple superimposed small harmonic content inverter output voltage waveform, That THD is small, but the circuit is more complex. The PWM pulse width modulation inverter, both the computer's circuitry, and the output voltage waveform, which has been widely used.

The so-called PWM technology (Pulse Width Modulation, PWM), is made of a reference wave (usually a sine wave, sometimes with a trapezoidal wave or injected zero sequence harmonic Electric transformer‍ sine wave or square wave, etc.) for the modulation wave (electric energy meter), and to N times the frequency of the modulation wave of the triangular wave (sawtooth wave is also sometimes used) of the carrier (Carrier Wave) waveform comparison, the modulation wave is greater than the carrier portion to generate a set of equal amplitude and a width proportional to the modulated waves equivalent rectangular pulse sequence is used to modulate the wave instead of using analog switch, and through the inverter power switch on / off control, the DC power into AC power, this technique is called pulse control inverter technology. Because triangular carrier wave (or sawtooth) vertical section is a linearly varying degrees, so this technique is called pulse control inverter technology. Since the triangular carrier wave (or sawtooth) is vertical width is linear, so that this modulation is linear, when the modulation wave is a sine wave, a rectangular pulse width of the output pulse train changes sinusoidally, this modulation Air circuit breaker‍ technique typically also known as the sinusoidal pulse width modulation (Sinusoida PWM) technology.

Voltage stabilizer Inverter FAQ

u outside interference

The inverter may be due to a number of occasions in the strong electromagnetic interference, such as motors, power inverter, a strong magnetic field in the vicinity.

Far away from the device similar to circuit breakers‍ the above.

u inverter does not respond

1. Battery and the inverter is not connected, reconnect.

2. Battery pole reversed, the fuse is blown. Replace the fuse.

u output voltage is low

1. Overload, load current exceeds the nominal current, turn off some of the load restart.

2. Input voltage is too low. Ensure input Cncelegroup‍ voltage is within the nominal voltage range.  

electric energy meter Inverter include:

Dedicated power inverter

Communications for power inverter   

Frequency inverter powered

Industrial sine wave inverter

Square wave inverter

The role and characteristics of medical Inverter

Due to a variety of different types of medical equipment supply needs, use the most is the centralized power structure. I.e., by a power converter to produce the desired concentration of various voltage air circuit breaker‍ levels of the output voltage. Due to its low cost, high efficiency, adjustable output voltage electric energy meter, low output noise, fast dynamic response and other type of equipment is very suitable for medical use, is a medical device is currently the most used type of a power supply. Medical equipment supply program to determine the need to consider the following questions.

Security and isolation is a major difference between the ordinary commercial power and medical supply. Typically, in addition to some experimental analysis class equipment, medical equipment mostly installed near the bed or the operating table, and the operator's distance from the more recent, the shell will often be Circuit Breakers  ‍touched. There are a variety of medical equipment inside the strong, weak parts, if the strength of electrical isolation between the insulated shell material or have a problem, it will be very dangerous. General medical equipment safety testing power supplies must be UL60601-1, C-UL, EN60601-1 safety certification. Inputs and outputs must be more than 4,000V isolation voltage, and low leakage current requirements to meet safety creepage distance requirements. And part of the need for a strong electric double insulation, especially some of them might be more in contact with the enclosure designed to enhance insulation.

Electromagnetic compatibility and immunity to electromagnetic interference

Select the type of equipment to be medical or build a good power supply system must focus on improving the supply of electromagnetic compatibility and electromagnetic interference. CNC Electric‍ Mainly from the following aspects to consider: design. PCB design and layout, in general will contain some of the high frequency power signal, any traces on the PCB can be functioned as an antenna, the length and width of the printed lines will affect the resistance and inductance, thus affecting the frequency respond in a timely manner will be coupled to the RF signal and cause problems through the circuit traces DC signal from adjacent tracks. Medical power supply must be selected so that the big brands, has a strong R & D strength of the company's products, which in the design and production processes can ensure good quality.

Shield

In order to suppress the switching power supply generated by radiation, eliminate the influence of electromagnetic interference from other electronic devices in the medical equipment electric energy meter‍, the best way is to supply the magnetic shield, the shield and then the entire cabinet or medical Power Transformer‍ devices to a single entity, this is a more effective approach.