Industrial power supply is widely used, which is different from adaptors and other power supplies (using a single load, simple application site), the use of many types of equipment, the use of complex environment (indoor, outdoor, damp, dust, high temperature, low temperature vibration, etc.) The use of many types of load (capacitive inductive resistance static, dynamic overload, etc.) equipment is basically industrial equipment with high use frequency and long use time (some sets) Standby is used 24 hours a day, so the safety and reliability of the equipment, life has high requirements. The main factors that generally affect the quality and life of switching power supplies are as follows:

(1) Design quality: The design quality will reflect the initial use or under certain application conditions, the power supply batch damage or unusable. No industrial power supply application and design experience. Dominant factor

(2) Material quality: The quality of the material will be reflected in the entire use process, the quality of semiconductor materials will generally appear in the early use, capacitive materials will generally appear in the early, middle or end, accounting for the main factor

(3) Process quality: The quality of the process will reflect the basic control of the occasional failure of the initial power supply - a secondary factor

(4) Field application: batch damage of the power supply under some uncontrollable environmental application conditions - the power supply design does not consider these abnormal factors as the main factor (5) Customer design: the load or temperature used by the customer for a long time exceeds the specification, resulting in uninterrupted damage ---- Strengthen the communication service during the selection of customers is a secondary factor.

MTBF: means TIME BETWENT FAILURE At present, the most commonly used prediction methods of MTBF are Part count method and Stress Analysis method. The most important regulations followed are MIL-HDBK-217F Notice 2 and TELCORDIA SR/TR-332/Belcore, where MILHDBK-217F Notice 2 is the United States Military code and TELCORDIA SR/TR-332(Bellcore) is the general business code called MTBF(Mean Time Between The average time to Failure is the expected value of the reliability estimate. The average time for the reliability of the product to fall to 36.8% after continuous operation for a period of time.

(a)85~264VAC120-370VDC(b)176-264VAC.250-370VDC:C)85132VAC/176-264VAC By Switch; 250-370VDC If the above o is marked, both AC and DC power supply (AC *1.414) at the input end can work normally. However, pay attention to whether there is positive +) negative) wiring requirements in the specifications. If the above C is marked, 115/230V must be switched to the "230V" position before input 250370VDC If the switch position is "15V" and 250-370VDC is sent, it will cause damage to the power supply.

There are several reasons for the power supply to crash in use :(1) overload protection: the load exceeds the rated load instantaneously and exceeds the overload protection point, resulting in overload protection. It is recommended to increase the output power of the power supply or adopt a constant current limit power supply. (2) overtemperature protection: The ring temperature is too high during use. Need to improve the heat dissipation mode or choose another type of power supply (3) Overvoltage protection: If the load is inductive, an external voltage may be injected into the output end, resulting in overvoltage protection.

That is, the voltage Test (Hi-Pot Test) or electrical strength test (Electric Strenath Test) should be short-circuited to one point before the nout terminals (/P)0utput terminals short-circuited to one point

(O/P), FG can be tested only after a single point according to the following test loop between the specified terminals (I/P.O/ P.G) voltage resistance test (for example, when the test voltage is AC, the leakage current is generally 25mA as the reference voltage rise time 1S test time 1 minute)

(1) The voltage test is to ensure that the primary and secondary insulation of the power supply is good to avoid the danger of electric shock. The test voltage must be gradually increased from zero to the maximum voltage (rise time of at least 1 second), and stay at this point.

If the leakage current increases rapidly due to the application of the test voltage, it means that the insulation breakdown has occurred; A corona discharge or a single momentary flash is not considered to have broken down the insulation.

(2) When using AC voltage test Y capacitance is the main cause of leakage current, the general leakage current is set to 25mA(the current safety regulation does not define the limit value of current) Our factory test leakage current is set to 10mA.

CLASS1: Such equipment means having protection against electric shock through the use of basic insulation, in addition to providing a protective ground impedance connected to the building. When the basic insulation fails, This grounding impedance will withstand dangerous voltages to the ground -CLASSI's Schensource supply provides ground-connected terminal CLASS: Such devices not only rely on basic insulation for protection against electric shock, but also must provide additional safety measures of double insulation or reinforced insulation, and there is no power supply that relies on ground protection -CLASS Ground connection terminals CIoss 2 will not be provided: When the electronic circuit is powered by LPS(limt Power Source), the current and energy of the circuit can reduce the risk of fire below the specified standard values as required in UL1310 standard.

Not necessarily, the position of the general power supply in the system, the arrangement of the wire group and the grounding design of the system will cause some degree of impact. The same power supply will often have different results in different use environments or applications. Our test results are based on the Settings in the EMC test report.

Because our products are isolated design, your company's system (V) and ground FG) are basically connected together, there is no problem in safety regulations, but you should pay attention to the impact of EMI.

Our power supply can be used at altitudes greater than 2,000 m (6,500 ft) with reduced load as follows:

(1) The ambient temperature of the fanless model decreases according to the ratio of every 35C/1000m

(2) The ambient temperature of the fan model decreases according to the ratio of every 5/1000m

Since the power supply needs to pass the regulations of EMI, the input end of the switching power supply will add some Y capacitors to the ground (housing) connection for filtering. The capacitance characteristic is to isolate the through-alternating input end for AC AC. All leakage current causes the housing to be charged. This is a safety project, if the product has passed the safety certification leakage current is in line with the regulatory requirements will not cause harm to the human body, the product as long as the correct grounding can be solved.

(1) Temperature control type and load control type design purpose is mainly to improve the life of the fan;

(2) When the equipment is running, the fan is used for heat dissipation. When the equipment is in standby mode, the load is small, the power supply temperature is low, and the fan stops, which can reduce the noise of the equipment.

(1) If the industrial power supply uses inductive load (such as motor motor), there will be an instantaneous voltage superposition when the rotation direction changes or the shutdown moment. Some will cause abnormal power shutdown or OVP voltage regulator damage phenomenon: for example: normal 24V output power supply, output voltage warm room will have 48V phenomenon, if the power supply OVP design point is too low or OVP current limiting positive is too small will cause OVP stability tube damage, if the OVP protection mode is shutdown mode, some devices will suddenly shut down. Need to restart the input voltage of the equipment (2) Industrial power supply from MASP, fully considering such applications, the output OVP protection mode is self-recovery while ensuring that the output is not damaged when the external voltage is superimposed to ensure the stability of the equipment.

(1) There are many application scenarios of industrial power supplies, and there are many load types, some are inductive, some are capacitive, some are resistive, and even some are a combination of various load characteristics;

(2) The characteristics of capacitive and inductive load are that the instantaneous voltage and current cannot be sudden, which will lead to a large current at the moment of startup, and a small rated load after startup;

(3) Overload protection is designed for HICCUP mode, when encountering capacitive and inductive loads, problems such as failure to boot normally sometimes occur. The customer's approach is to choose a more powerful power supply, which will increase the cost;

(4) The protection mode of the output constant current limit design can avoid such problems, no matter how capacitive and inductive load boot will not cause the phenomenon of failure to boot, Can greatly save the customer's selection cost example: some customers use 24V/450W industrial power load for PLC+ control board test startup instant current is 15~16A, after the startup current is 1~3A, before using the * brand 350W power supply can not be turned on, and then choose 450W power supply according to the application method to choose back MPA-100-24(100W) can completely replace the above 450W power supply so that the cost advantage will be obvious.

(5) Constant voltage constant current power supply, can achieve the effect of parallel use to improve the output power, although compared with products with parallel modules, the current sharing effect is relatively weak, but does not affect the use of customers and may be more advantageous delivery time is better, after all, the customer base of high power supply demand is not large.

(1) In order to make the system more stable, lower failure rate longer life of the power supply It is recommended that customers choose the output power of the power supply is larger than the actual load power, it is recommended that 20%~30% margin for example: the actual working rated load of the equipment is 100W it is recommended that customers choose the output power is greater than or equal to 120W products.

(2) It is necessary to consider the ambient temperature of the actual work of the switching power supply and whether there are additional auxiliary cooling devices. If the ring temperature is too high, the overtemperature protection life may be shortened, and the power supply failure may be caused

The temperature load curve of the grid book evaluates the actual application mode,

(3) Choose models with complete protection functions to ensure the stability of products and systems

(4) Choose big brands with product certification to reduce safety risks:

(5) If the load is a motor, motor, large capacitive load, in order to ensure the system temperature, it is recommended to choose the overload design for constant current type products

(6) If the power distribution of the equipment site may have input voltage instability, such as industrial power, outdoor power and other places, it is recommended to choose products with input voltage overvoltage protection. 

(7) If the equipment site has high dust, humidity, etc., it is recommended to choose moisture-proof or glue-filling products.

(8) If the equipment has high noise requirements, it is preferred to choose products without fans.

(1) Many application scenarios of industrial power supply are generally industrial electricity and outdoor electricity.

(2) Industrial power grids and outdoor power grids will have instability (such as zero line) and three-phase imbalance and other problems resulting in high input voltage phenomenon, ---- these are irresistible factors.

(3) The startup of large equipment inside and outside the factory will also cause the phenomenon of three-phase voltage imbalance - these are irresistible factors.

(4) Through the analysis of the repair status of the peer industrial power supply market, the proportion of damage to varistor high-voltage capacitance and MOS due to high input voltage reached more than 70%, and some of them were repeated back and forth.

(5) Product export consideration due to the instability of the power grid in many developing countries and less developed countries to reduce after-sales problems.

(6) In order to ensure the stability and brand value of customer equipment, our products have improved the voltage level of components, increased the cost to improve the reliability of products, and added value for customers.