MEAN WELL power products have been widely used in various electronic equipment, including industrial control, information, communication, home appliances, medical, lighting, billboards, security and transportation, etc., which can meet most of your needs!
What are the key points to pay attention to when using power supply cables?
When installing a power supply, both the input and output terminals need to be connected by wires, and the selection of wires needs to consider two points. The first is the problem of current resistance, because if the current resistance is insufficient, the temperature of the wire will be too high or even burned The first is the problem of voltage drop. Because the wire itself has impedance, it will cause a voltage drop when the current flows. If the voltage drop is too large, the voltage at the load end will be too low, which may cause the load to fail to work. Based on your actual system design, you can refer to the following recommended table for the current drop of the wire.
How to choose AC plugs in different countries using your adapter products?
Adapter (Adaptor) usually needs a power cord to provide its required power, and the corresponding end of the end of the power cord connected to the adapter can be selected by referring to the AC INLET model in the adapter specification; as for the plug connected to the power outlet The voltage or voltage will vary according to different countries. You can refer to the following table of voltage and plug comparison for each major business travel country to choose. Note: 1. This plug set cannot convert voltage 2. Although this comparison table distinguishes plugs by country and voltage, there are still different countries in the same country due to different regions and different voltages and plug types. Therefore, please confirm before using.
What should I pay attention to when using the remote detection function?
First, please follow the following configuration diagram, connect + S to the positive end of the load, and -S to the negative end of the load. The wire must be twisted and away from the power line to avoid noise interference. In addition, if the load is a dynamic load (frequency is greater than 1kHz), because the noise at the load end changes greatly, it is easy to interfere with the remote detection function. It is recommended that a capacitor be connected to the load to suppress this noise; the capacitor should be selected to ensure that its rated ripple current is greater than 0.2 times the load current and its rated voltage is greater than the load voltage.
If the built-in curve of Mingwei Smart Charger cannot meet the battery specifications, can I set it by myself? (With video)
Yes, SBP-001 can be applied to Ming Wei's intelligent programmable chargers through editing software, such as ENC series, RPB series and RCB series. Through this hardware interface, a link communication can be established between the charger and the computer. The functions provided are
Charging curve adjustment: constant current value, constant voltage value, floating charge voltage value and decreasing current value can all be set and adjusted.
Battery temperature compensation: Provide different charging voltage compensation according to different battery temperatures.
Charging timeout setting: Set the time flag to protect the battery from overcharging.
For detailed configuration and settings, please refer to the user manual of SBP-001:
What should I pay attention to if a strong magnet is installed in the system?
When the customer's system uses a powerful magnet for convenience or quick maintenance, it is recommended that the location of the powerful magnet be kept away from the power supply to prevent the powerful magnet from interfering with the internal magnetic components, which may cause the power supply to trigger protection or damage. If the space is limited and you cannot get away, it is recommended to install a high-permeability metal plate (such as steel plate, iron plate ...) between the power supply and the powerful magnet to reduce the interference of the powerful magnet on the magnetic components.
How do I choose a power supply for battery charging?
MEAN WELL currently launches ENC, HEP-600C, GC, PA, PB, RPB, RCB and other series products (30 ~ 1600W) for charger products. If the charging requirements mentioned above are insufficient, other models must be selected. For other models, it is recommended that the power supply overload protection function (OLP) selected be the constant current mode. Because when the battery is out of power, the output current of the power supply will increase with the degree of battery exhaustion and the capacity of the battery. At this time, there is a great opportunity to trigger the protection circuit of the power supply. If the overload protection mode of the model is Hiccup or shutdown, it will interrupt the charging of the battery. As the overload protection mode is constant current mode, it can continuously maintain a certain current to charge the battery, but because it is overloaded, it is recommended to use Modify the overload protection action point. Please contact Mean Well if you need it.
What are the applications for tandem?
There are two applications of series connection of the power supply, one is the application of positive and negative voltage; the other is the application of increasing the output voltage. The connection method is as follows:
(1) The connection of positive and negative voltage is as shown below.
(2) Increase the output voltage (current is not changed). A diode must be added to the output end of the power supply to prevent internal damage to the power supply during startup. The withstand voltage of the diode must be greater than V1 + V2 (as shown below), and the instantaneous current must be greater than the rated output current.
Configuration requirements for the parallel function?
Power supplies are used in parallel, in addition to increasing the output current, some models even have a backup function. Pay attention to the error of output voltage and wiring impedance when paralleling. Also note the following:
1. Connect the P (LP / CS) points together, such as PSP models (please refer to the description of the parallel function in the specification book). Input / output must be connected in parallel before connecting to the load as shown in the figure below. (Some models require a minimum load requirement in parallel)
2. Adjust the output voltage error as close as possible (error is less than 2%).
3. Each unit must be connected with thick and short wiring before being connected to the load.
4. After parallel connection, the output is 90% of the total wattage of the parallel connection.
5. SPS is used in parallel. If the total output load is less than 10% of the rated current of each SPS, some SPS indicators or power signals (Power Good, Pok, Alarm Signal) may malfunction.
6. In order to ensure the shunt effect in parallel, the total number of parallel use is generally limited to 4-6.
7.Some models need to connect + S and -S of the Control Connector together to reduce the output jitter.
Why does the power supply fail to start when the load is a motor, light bulb or capacitive load?
When the load is a motor, a bulb or a capacitive load, the current is too large at the moment of starting. The recommended power protection method for the power supply is a product designed with a constant current method.
Our company's system uses the output terminal ground (GND) and the ground (FG) as the common point. Is it feasible to apply your company's power products?
Yes, because our products are all isolated designs, your company's ground and frame ground are basically mated together. There is no problem in safety regulations, but pay attention to the impact of EMI.
When using your company's products, it is found that there is voltage on the case. Is this normal? Will it cause human injury?
Due to the EMI requirements, the input end of the general POWER SUPPLY will be connected to the FG (case) through some noise filtering capacitors, causing the phenomenon that the case is charged. And this kind of phenomenon also has clear regulation in IEC60950-1, for example: The leakage current of the information equipment must be lower than 3.5mA, and can be solved as long as it is properly grounded.
Is it possible to reduce the noise of the fan of the power supply because of the requirements of the application?
The built-in fan of the power supply has a direct relationship between the part that dissipates heat and the noise it generates. If the fan's noise (exhaust volume) is reduced, the heat dissipation capacity is also reduced. This aspect will affect the reliability of the product. In addition, when the product is certified for safety regulations, the selection of the fan is also limited to the setting of the minimum exhaust volume. When changing the fan of some products, the safety agency must be supplemented according to the definition of safety regulations. The filing acknowledges that a smaller airflow fan can be used only after passing the test. If the customer's system is concerned about noise, it is recommended to use fanless products instead; or contact MEAN WELL, which may be modified according to customer conditions.
The power supply is generally placed horizontally and vertically. What should be paid attention to when using the product?
Most of the low-power internal fanless power supplies are designed to be placed horizontally. If the system mechanism is problematic, the power supply should be placed vertically, because the output power should be considered at higher ambient temperatures Reduced use (refer to product specifications). As for the models with a cooling fan inside the power supply, there is no difference in the placement method for horizontal or vertical, or the application system has a separate forced cooling fan to provide proper cooling of the power supply. No difference. Ex. SP-150 product derating curve, general horizontal / vertical application environment temperature difference is 5 ° C, and there is 20% output power difference between forced heat dissipation and natural heat dissipation.
Can Mingwei's charger be used in lithium batteries or other types of batteries?
All Mingwei chargers are designed for lead-acid batteries. Each lithium battery or other type of battery has its charge and discharge characteristics, so it is necessary to modify the charger of Mingwei to meet the settings required by each battery or user. If necessary, please contact your local distributor.
In the LED lighting design, if the LED light bar design uses 12 LEDs as a string (VF is assumed to be 3.5V), 4 strings are connected in parallel, each string of current is 0.7A, directly connected to the power output without constant current How do I choose a suitable power supply for the driver?
First, make sure that the LED power supply needs to select a power supply that can work in the constant current mode. Each string of LED working voltage = 3.5VX 12 pieces = 42V LED lamp total demand current = 0.7AX 4 series parallel = 2.8A LED power demand wattage = 42V X 2.8A = 117.6W The wattage / voltage selection of the LED power supply should be greater than and the closest to the required wattage / voltage. Select the LED power supply with 150W / 48V demand, and then confirm whether the selected voltage / wattage power supply is used. Meet the requirements of the constant current interval and PF> 0.9. (117.6W / 150W = 78.4%> 75%) For example, you can choose CLG-150A-48V to adjust the output current to 2.8A. Note: Generally, the VF voltage of the same batch of LEDs may be in a range (such as 3.4 ~ 3.6V). There are differences in LEDs, and this difference needs to be considered in the selection of power supply
Same as the previous question, how to choose a suitable power supply if the LED light bar is to be connected in series with a constant current driver in the lighting design?
First confirm the total forward voltage of each string of LEDs, plus the cross-voltage of the constant current driver of about 2V. The working voltage of each string of LEDs = 3.5VX 12 pieces = 42V drive circuit voltage = 42V + 2V = 44V LED current = 0.7AX 4 Series and parallel = 2.8A wattage of drive circuit = 44V X 2.8A = 123.2W The wattage / voltage selection of the LED power supply should be greater than and closest to the required wattage / voltage. Select the LED power supply with 150W / 48V demand first , Then confirm whether the actual wattage of the drive circuit meets the definition of PF> 0.9 (123.2W / 150W = 82.13%> 75%) For example, you can choose CLG-150A-48 and adjust the output voltage to 44V or you can use it directly .
Why sometimes the LED power supply cannot be turned on smoothly when there is an LED driver IC in the LED string design (the voltage is clamped by the LED and cannot rise to the rated voltage)
Depending on the circuit used, there will be different operational issues as follows:
- Boost Mode Current Driver IC
Because the start-up voltage of the driver IC is far lower than the forward operating voltage of the LED string, the driver IC starts at low voltage. Often, the IC start-up voltage is even less than half of the power supply voltage. At this time, if the rated power output is to be reached The driving current must be at least 2 times the rated current of the power supply. Therefore, the LED constant current module cannot be driven because the power supply cannot provide such a large current.
- Buck Mode Current Driver IC
When the output voltage of the power supply is much higher than the forward voltage of the LED string (for example, when the power supply outputs 48V and the LED string is only 24V and the power between the two is equivalent), the LED power supply is supplied when the power is turned on and the LED starts to turn on. The device immediately enters the constant current operation mode. Because the power consumption of the LED at this time is set to be much larger than the driving capacity of the constant current of the power supply at this time, the driving circuit cannot work normally, and the power supply voltage is clamped under the forward voltage of the LED string. . Therefore, it is recommended to increase the start-up voltage of the driver IC close to the power supply output voltage or add a slow start function (see Figure 3) when the LED driver is designed, and then start the drive module after the power supply output voltage is established. Or when selecting a power supply (used in a step-down module), you must choose a power supply with an output voltage close to the LED string voltage, and the driving power must have a margin of power (LED consumption power / 0.85).
The DIM PIN is a PWM dimming control PIN. It is also marked as EN (Enable). When the DIM (or Enable) remains at 0V, the internal SW is turned off. When the DIM voltage reaches 1.5V (Typ), it turns on. Therefore, set the start voltage Vstart of DRIVER: Vstart = (VDIM / RB) x (RA + RB), Vstart is set to be 5 ~ 10% higher than the working voltage of the LED.
Can LED power supplies be used in parallel?
MEAN WELL LED power supply has no parallel function and cannot be used in parallel. If there is a large wattage requirement, it is recommended to choose a sufficient power supply or divide the LED into several blocks to supply power separately. As shown in Figure (5), separate the output ground circuit of each power supply. Conversely, a small wattage LED string can be connected in parallel and then driven by a larger rated LED power supply (as shown in Figure 5), but its current sharing must be considered.
What is the maximum tolerance of Mingwei LED power supply for lightning surges?
In the Mingwei LED power supply product line, the highest lightning surge withstand capability is CEN, CLG and HBG, HLG, HLN, HLP, HVG, HSG series products, which can reach the heavy industry level (4kV). The SURGE tolerance needs to be as shown in Figure (8), and then connected with ZNR (470V) or Gas Tube (500V) countermeasures, but the overall safety requirements must be considered. In the application of multiple lamps, in order to meet the requirements of regulations, a lightning protection device (SPD: Surge Protection Device) can be added.
Can I recommend a dimmer with 3 in 1 dimming application?
3-in-1 dimming is the most widely used dimming product of MEAN WELL. It does not need to be matched with a specific manufacturer's dimmer, as long as the specifications of the dimmer (voltage 1 ~ 10V / 10V PWM / resistor) can meet the definition of the specification. Can be used together.
Which product should I choose with light bar dimming?
Because general LED string lights have series resistors, the LED power supply must be driven at a constant voltage. It is recommended to use a constant voltage dimming model, such as the PWM series.
How do I know that a dimming device can control several 3 in 1 dimming products?
The 3-in-1 dimming product has a load current of 0.1mA. Divide the rated current of the dimmer by 0.1mA to know how many products can be controlled. In the application of resistance dimming, the resistance value at 100% dimming output 100Kohm divided by the number of units.
Can LED constant current products be used as chargers?
There are many choices of MEAN WELL charger products. Customers are recommended to choose MEAN WELL charger products first, because charger products are considered for charging applications regardless of safety regulations or product testing. The products will meet the requirements. Find the right product. Mingwei LED constant current products can be used for constant current charging. Customers need to choose the suitable product according to the battery charging current and voltage.
With so many Mingwei dimming products, how do I choose? What are the advantages and disadvantages?
MEAN WELL LED dimming products will be designed according to the lighting application occasions or market requirements. It is recommended to first select the LED products according to the lighting application category, and then select the dimmer according to the original product's dimming method. If the application is not considered, The advantages and disadvantages of the single comparison dimming method are as follows.
Can MW LED products be used at full load? Should they be reduced by 70% like normal power supplies?
MW LED products can be used at full load without problems, but the annual warranty model has a defined Tc temperature limit. If the LED power supply is placed in a high temperature environment and there is a 5-year warranty requirement, it needs to be used under load.
Can LDD / LDH products be used in series and parallel applications?
The output of the LDD / LDH series is connected to the internal switching components of the product. If the output is used in series and parallel, the product will be damaged.
What is the maximum input and output cable length of LED products?
In the case of considering line loss, it is recommended to lengthen the input end line length application. If the output end line length is to be lengthened, it is necessary to confirm whether the line loss will cause the lamp to malfunction due to insufficient driving voltage. Increasing the line length will affect the EMC characteristics of the product. Reconfirm the EMC characteristics.
Why do we use a Mingwei LED power supply, the LED has a slight change in brightness or flicker?
MEAN WELL launched a series of products for LED power supplies. Some chose to use a single-stage PFC circuit architecture due to cost considerations. This architecture has the following restrictions:
- Ability to resist AC changes This architecture does not use large input capacitors. If it is used in areas where the input power quality is unstable, the output voltage and current will also be unstable, which will cause the LED to change light and dark. If the input power is stable, it will not change. This issue has occurred.
- The output ripple voltage is also because the input does not use large capacitor filtering, the output ripple voltage will be larger than the general two-stage PFC structure, as shown in Figure (4). Sometimes the valley of the ripple voltage is too low, which causes the LED to flicker due to insufficient driving voltage when the series constant current IC is applied. At this time, the output voltage of the power supply can be increased to make the valley of the output voltage higher than the required drive. Voltage or select a power supply with a higher voltage output.
- Harmonic current
When a single-stage PFC power supply is used in a constant voltage condition (referred to as a series constant current IC), the harmonic current may deteriorate.
Why can't I use MW LED dimming power products to be dimmed?
First confirm the driving method of the lamp. If it is a constant current lamp, you need to confirm whether the LED series voltage is within the constant current range defined in the specification. If it is a constant voltage lamp (for example: LED string), check whether the correct adjustment is selected. Optical products, constant voltage drive must choose PWM and other products.