BATTERY: INDUSTRIAL CHARGER & PROGRAMMABLE POWER SOURCE

With the democratization of mobile devices, the drop of manufacturing cost of batteries, as well as the growing awareness on environmental topics issues, the technology of batteries and chargers has witnessed a tremendous breakthrough in the past few decades; numerous of new batteries have seen the light of day, and innovative charger applications are born as accompaniment.


From Electric Vehicle Charging (EV Charging) infrastructure to Energy Storage System (ESS), the modern chargers are utilized in numerous different sectors nowadays and are pushing the society further towards the more sustainable and renewable energy options.

HOW CHARGER IS DIFFERENT FROM REGULAR POWER SOURCE

While common Power Supplies are designed to provide a fixed and constant DC voltage, chargers require a more complex design with different charging phases to assure the longevity of batteries and safety during operation.

To meet the specific charging needs of different types of batteries, industrial chargers are generally designed with several charging phases, including principally a boost voltage-constant current phase, a constant voltage phase, and a float voltage phase.

More advanced industrial chargers use a microcontroller (MCU) design, which detects the charging status of the connected batteries and allows further adjustment between different charging phases.

Nevertheless, it does not mean that chargers are the only option for charging applications nowadays. Advanced technology in power supplies has made it possible to adapt a programmable power supply, with adjustable voltage and current, to the specific charging demands in the field too.

 

HOW TO CHOOSE YOUR CHARGER

Choosing the adequate DC power source for the battery is critical if one wishes to maintain the battery’s performance. In the following paragraphs, we will be listing down a few criteria which are considered essential when it comes to the selection of proper chargers for the system.

 

A. Battery Charging Profile

Each battery type has its own specific charging needs and requirements. These requirements are normally defined by the battery manufacturer and listed in their specification. Hence it is important to start by identifying the battery charging profile before further diving into choosing the suitable charger. For the 2 most popular battery types used, we listed 2 example charging curves below:

 

  • Lead-Acid Battery requires chargers with minimum 3 charging stages. 
lead acid battery stage 1

Image 1: Three Stages for Lead-Acid Battery

  • Lithium-based Battery requires generally chargers with 2 charging stages: first with constant current, followed by constant voltage.
lead acid battery stage 2

Image 2: Two stages for Lithium-based battery (LiFeP04, LiCoO2)

For more information read our “Lead-acid and lithium battery charging” article.

For more information about selecting the right charger for your battery please refer to our  “Selecting a charger from your battery” article.

Tip: MEAN WELL offers a Smart Battery Charging Programmer (SBP-001) which allows users to configure via a user-friendly interface, the charging curve of selected MEAN WELL chargers and power supplies (e.g. Intelligent RCB-1600 charger, HEP-1000 for Harsh environment, ENC…etc.). With SBP-001 programmer, the user can set the output current and voltage to further simulate the charging curve for different batteries.

Intelligent Charger DBU-320

Image 3: Intelligent Charger DBU-3200, configurated via SBP-001 and its user-friendly interface (Click to download)

B. Regulations

According to International Electrotechnical Commission (IEC), numerous regulation standards exist for the purpose of ensuring safety, efficiency, reliability, and interoperability of electrical, electronic, and information technologies; depending on the application of the end device, the mandatory regulations can differ from one to another.

For instance, IEC/EN 60335-1 is the basic requirement for Household appliances’ design, aiming to prevent foreseeable hazards ones could encounter when using the end device. Furthermore, IEC/EN 60335-2-29 defines the requirements in detail for battery chargers intended for household battery charging.

Specific charger applications such as AC EV Charger might require an additional power source to power the auxiliary and communication modules inside the such charger. For these kinds of applications, one has to evaluate on the system level if power supplies with more strict requirements are needed, such as the IEC/EN 61558-1 certification and compliance with OVC III (Overvoltage category III) protection level. Power Supplies with OVC III compliance can be integrated without adding an extra isolation transformer on the input side and gives your products the best out in terms of flexibility and costs in a minimized space. In addition, using such power supplies in AC Charters gives greater flexibility in terms of installation as these would allow the charger to be permanently connected to a distribution panel.

As for chargers intending to power up UPS systems and battery test systems, IEC/EN 62368-1 and IEC/EN 62477 are generally the safety regulations to comply with.

In addition, the standards related to electromagnetic compatibility (EMC) emission and immunity are equally important to take into consideration. In case the charging system is certified according to the IEC/EN 62368-1; the EN 55032 and CISPR 32 standards must be confirmed; in case the system needs to be certified for the IEC/EN 60335-1, the emissions and immunity according to the EN 55014 have to be met. Other major EMC regulations which must be complied with are the IEC/EN 61000-3 and IEC/EN 61000-4.

Therefore, clarifying the specific requirements for safety and EMC regulation standards will greatly facilitate the selection of the battery charger process.

Safety Regulation No. MEAN WELL Series
EN62368-1 HDR-15/30/60/100/150
ENC-120/180/240/360
NPB-120/240/360/450/750/1200/1700
RPB-1600 / RCB-1600 / DBR-3200/ DBU-3200
HEP-600C
CSP-3000
PHP-3500
RST-10000/ 5000
BIC-2200
TDR-240/480/960
WDR-60/120/240/480
Adapter Charger: GC30/120/160/220/330
OVC III (based on EN61558) HDR-15/30/60/100/150
*PHP-3500
OVC III (based on EN62368) IRM-30/45/60/90
EN60335-2-29 / EN60335-1 NPB-120/240/360/450/750/1200/1700
EN60335-1 IRM-60/*90
*PHP-3500

*=Regulation Designed Ready, NRE needed by users request

C. Installation

The working environment and condition are essential to the reliability and lifetime of both battery and charger; engineers must take into consideration the eventual working and storage condition of the battery charger to further choose an adequate model for the design.

For instance, chargers designed as 5G vibration-proof are more suitable for installation located in a mobile device. E.g., wheelchair, E-bike, mobile working station, camper van…etc. Whereas waterproof and dust-resistant IP67 chargers and power supplies are generally recommended for application under humid and dusty environment, both indoor and outdoor. 

On the other hand, it is not to forget that the working temperature is equally important to the longevity of battery charger and battery as the other working conditions mentioned earlier. Therefore, one should think about selecting a power source with adequate thermal dissipation design (e.g., convention cooling, forced air flow, conducted colling, water cooling…etc..) for the system too. 

Last but not least, the selection of battery charger is sometime limited by the available space or specific installation method too; a 19-inch rack cabinet will probably need an 1U Battery Charger (e.g., 1U-tall RCB-1600) to save space and a DIN Rail cabinet will most likely adapt a DIN RAIL power source (e.g., HDR series with OVC III  protection)…etc.  

Future postings and articles:

In the upcoming future, MEAN WELL will also share its knowledge regarding the booming Energy Storage System (ESS) field. For instance, how to use MEAN WELL Chargers (programmable 67~400VDC) in a High Voltage Direct Current (HVDC) application, as well as the know-how on digital communication protocols (e.g., PMbus and CANbus), which can further perform voltage and current control for the Energy sector. 

LEARN MORE ABOUT CHARGING POWER SUPPLIES

Explore our blog for insightful technical notes about Charging Applications.

Got questions?

Look at the section below to find the most frequently asked questions (with answers)
we received in Charging Applications.

The GTIN number can be found directly on the www.meanwell.com:

Tags: EAN, Gtin

Yes, MEAN WELL products are registered in SCIP. To get such information for specific power supply, please follow the steps below:

  1. Go to https://echa.europa.eu/en/scip-database
  2. Under SEARCH option, choose „Article Identity” and write down model name e.g. RSP-1600.
  3. As “Identifier type (optional)”, please chose “Other”
  4. Click “Search” button
Tag: SCIP

The declaration of Five PBT TSCA Conformity can be found on the last page of Installation Manual e.g. below:

Tag: EPA-TSCA

A Surge Protection Device is optimized for a single voltage. Therefore, SPD should be chosen according to the actual operating voltage of the part that need to be protected.Secondly, the voltage protection level shows what is the maximum voltage appeared at output side when a specified surge is coming to the SPD. In general, the lower the voltage protection level, and the higher the discharge or surge current from SPD, means the better protection that the SPD provides.

Owing to line (voltage)-drop, we suggest the extension made from AC cable. In case DC cable extension is necessary, please consider Line-Drop leading to insufficient Vf so that the LED model or lamp may fail to switch ON. Moreover, EMC performance and characteristic may also be affected by DC cable extension.

Categories: LED Lighting, Others

First, you have to know your Led lamp specification in order to screen out a suitable Led driver range (Wattage, Voltage, Max Current CC or CV). From those ranges, further check a compatible dimming function. Hereunder is a table to show you the pros and cons of Dimming Function you can find in MW’s catalogue.

Categories: LED Lighting, Others

MEAN WELL has several charger products, and we suggest choosing them first. Chargers would be more suitable since they are designed for charging applications. Safety and approvals should be taken into account based on the final application. If you are unable to find a proper model in our charger series, our LED CC models can be used as charger. Please choose suitable products after confirming the current and voltage specification on the datasheet of the battery.

Categories: Charging, LED Lighting, Others

3 in 1 dimming circuit would drain 0.1mA per model. Dividing the rated current of the dimmer by the 0.1mA, and we could know how many units can be controlled by one dimming device. For resistance dimming applications, resistance for 100% dimming output would be 100K ohm divided number of models.

Categories: LED Lighting, Others

A LED strip is normally a Constant Voltage application (CV). For this type of CV application MEAN WELL has design the PWM, IDLV and ODLV series which will allow CV applications to dim.

Categories: LED Lighting, Others

3 in 1 dimming is the most common application used in LED dimming with the feature that it does not have to work with any specific dimmer. The only thing that has to be verified is that whether the dimmer (1~10V/10V PWM/resistance) is compatible with the definition advised in our specs.

Categories: LED Lighting, Others

MEAN WELL’s LED product specification normally exhibits V-I characteristics. Per the characteristics, there are generally two types of drivers, the “CC” type and the “CC+CV” type. “CC” type of driver is suitable only for LED applications whereas “CC+CV” is for either LED applications or general switching power supply applications. The section that is not suitable for LED applications are represented by dotted line, and based on the protection procedures it can be categorized into hiccup mode and constant current mode; in this section, the tolerance of current is not defined but only the characteristic of current is displayed. If customers attempt not to see a very high current under short circuit conditions, those models with hiccup mode for this section can be selected; if there are applications with motors or capacitive load, those with constant current can be chosen.

Categories: LED Lighting, Others
Tag: CC+CV

There are 2 types of Power Factor Correction circuits; one is Single Stage; the other is Two Stage.

Single Stage power supply combines functions of power factor correction and converter in one circuit but Two Stage use two separate circuits. Compared to Single Stage, Two Stage design is more complex and costly, but the immunity performance of Two Stage power supply against AC mains is much better than that of Single Stage power supply. In addition, Two Stage power supplies manifest better ripple noises performance on output. Owing to that Single Stage is only suitable for fields with quality AC mains but Two Stage can be used in serious circumstances for LED drivers or as industrial switching power supplies.

Categories: LED Lighting, Others

Depending on the installation environment, you may need IP certified power supplies (IP65/IP67). 

Also, waterproof connectors and junction boxes are useful accessories to ensure a reliable operation in damp environments (please refer to the LED power supply installation manual).

Waterproof connector solution

Junction box option

Note that the MEAN WELL product IP level, including IP67, is tested according to IEC 60529. The protection does not guarantee for permanently immersing in the water. Please check the device installation manual for proper suggestions on installation. 

Categories: LED Lighting, Operation
Tags: IEC60529, IP65, IP67

MEAN WELL developed many power supplies series specifically for LED application. Single stage PFC was used in such developments due to low cost. This topology has the following restrictions:

AC fluctuation

  • This topology does not use input bulk capacitor. For this reason, in areas with low AC quality, output voltage and current may become unstable causing variation in LED brightness. If the input AC voltage is stable, then this problem will not occur.
  • Output ripple

This is also caused by lack of input bulk capacitor. As compared to power supplies using two-stage PFC, the ripple will be significantly larger (see Figure 4). There could be instances where the low end of the ripple may be too low for the driver IC to operate properly, and the LEDs will start to flicker. To solve this type of problem, the output voltage can be adjusted higher, so the low end is higher than the driver’s minimum working voltage. Or simply select a PSU with higher rated voltage.

  • Current harmonics

Single stage PFC power supplies are optimized for constant current drive. Using these supplies as constant voltage sources (such as application including cascading a constant current driver IC), the harmonics might be worsening in this case. When operating in areas with unstable utility voltage or with driver IC, we highly recommend using general application types as found in table 1. Avoid using single stage PFC if possible and use a two-stage PFC power supply instead, or contact MEANWELL for more information.

Categories: LED Lighting, Operation

MEAN WELL LED power supply does not have a parallel “current sharing” function, so it is not suitable for parallel connection. For high power requirements, please select higher wattage power supply or divide LED load into smaller subsections to be powered by individual power supplies. Example of such LED configuration can be found in figure 5. As shown in fig. 5, the connection between -V of the LPC-35 units should be severed and not connected in common. On the contrary, small wattage LED loads can be connected in parallel and be powered by a single high wattage power supply. But the ability to divide current evenly must be taken into consideration.

Categories: LED Lighting, Operation

LED power supply comparison table to see which MW LED power supply allows for V/I adjustments. A suitable unit can be picked based on the type of adjustment required. For the allowed adjustment range, please refer to the spec sheet. Tuning of the voltage and current levels can be done through the built-in VRs/potentiometers. PLN/ELN requires removal of the top cover in order to access the internal SVR1 and SVR2, see figure 9 for VR locations. For other series, the VRs can be accessed through IoADJ and VoADJ holes after rubber stopper removal. After adjustments have been made, please make sure rate power is not exceeded and the rubber stoppers are properly reassembled.

Categories: LED Lighting, Operation

With 1~10V dimming, the lighting unit can be dimmed down to 10%; with 0~10V dimming, it can be dim down to 0%, or say, dim-to-off.

Categories: LED Lighting, Operation

Depending on the circuit design, there could be different operational problems. See below:

  • Boost mode driver IC:

The startup voltage of such driver IC is significantly lower than the total LED forward voltage. For this reason, the IC will start up at very low voltage level usually about 1/2 of the power supply’s rated voltage and to meet rated power requirement, the startup current will reach 2 times the power supply’s rated current. When the power supply is unable to provide this current, the LED CC driver will not activate.

  • Buck mode driver IC:

If the selected power supply voltage is significantly higher than the LED forward voltage. For example, power supply provides 48V and the LED lamp only needs 24V and the power ratings are equivalent. When power supply voltage reached the LED conduction voltage, the power supply will immediately go into constant current mode. At this moment, the required power to start up the LED + driver is larger than what the power supply can provide causing malfunction of the driver circuit and the power supply to be clamped at LED forward voltage. For boost mode design, we recommend raising the startup voltage of the driver IC to be as close to the power supply voltage as possible or incorporate soft start function (see fig. 3). Wait until the power supply voltage is established before starting the driver. When selecting power supply for buck mode, the output voltage of the power supply should be as close to the LED total voltage as possible with excess power available (LED power/0.85).

DIM PIN is the startup pin for most PWM based driver. It can also be designated as EN (Enable). DIM (or Enable) is at 0V the internal connection to SW pin will be open. When the DIM voltage reaches 1.5V (Typ), the IC will Turn ON. To set the Vstart for the DRIVER IC: Vstart = (VDIM/RB) x (RA+RB). The general rule is to set the Vstart at 5~10% higher than the total LED forward voltage.

Categories: LED Lighting, Operation

LDD/LDH series comprises switching components; series or parallel connection will damage these switching components.

Categories: LED Lighting, Operation
Tags: Parallel, Series

First of all. Determine the driving method of LED lamp. If the lamp is driven by constant current, forward current shall be within specification. On the contract, if it’s driven by constant voltage, then user must check if they are using the right product to dim the LED lamp, such as PWM/IDLV/ODLV series.

Categories: LED Lighting, Operation

MEAN WELL’s specification shows the absolute values which were verified during design quality verification tests. Those condition are guaranteed by manufacture from quality and warranty perspectives.

When certifying a power supply according to a certain norm, there is normally a requirement described in this standard a certain tolerance which must be considered. (See also FAQ: Why Is The Input Voltage On The Label Different From The Input Voltage In The Spec? For Example, The Specification Shows Is 88~264 VAC While The Label On The Power Supply Says That It Is 100~240VAC?

The specification shows what is possible, the report and label of the power supply shows what is approved by the certifying body according to the standards.

Besides the difference due to tolerance there might also be another reason why the specification and label/test report show a different temperature. For example, if the power supply needs to be derated at a low voltage input such as 100VAC, the label and test report might show the max temperature at full load based on this low input.  

Different standards might have different tolerance requirements and different ranges this could mean that the most conservative value, or multiple values will show up on the label of the power supply.

MEAN WELL has incorporated dust proofing and waterproofing into the majority of its LED power supply design. Mainly based on the international standard IEC60529, detailed descriptions can be found in the following table:
(Note: PSUs with IP64 rating or above are suitable for indoor or outdoor applications in sheltered locations)

IP xy protection level

Degree of protection, foreign bodies (x)Degree of protection, moisture(y)
0.    Not protected
1.    Solid foreign object (>50mm)
2.    Solid foreign object (>12mm)
3.    Solid foreign object (>2.5mm)
4.    Solid foreign objects of 1,0mm diameter and greater
5.    Amount of dust that would interfere with normal operation
Dust tight
0.      Not protected
1.      Vertically falling water drop
2.      Vertically falling water drop when enclosure is tilted up to 15 degrees
3.      Water sprayed at an angle up to 60o on either side of the vertical
4.      Water splashed against the component from any direction
5.      Water projected in jets from any direction (12.5 liter/minute)
6.      Water projected in powerfil jets from any direction (100 liter/minute)
7.      Temporary immersion in water ( 1 meeter from the surface of the water for 30 minutes)
8.      Continuous immersion in water, or as specified by the user / manufacture

*IP64-IP66 level products are suitable for damp indoor or sheltered outdoor environment. For actual installation limitations, please refer to the corresponding IP level tests.
*All products cannot be continuously submerged in water.
*The definition of IP68 by MEAN WELL: Immerse a unit under test in 1 meter below the surface of the water, tested with a dynamic condition where 12-hour AC on; 12-hour AC off.
Test duration: 1 month.

MEAN WELL’s DMTBF can be found on www.meanwell.com

Please note that the DMTBF is not for every model available. Mostly this information is available for the LED drivers and our latest product releases.

1. Use the search function on the website to find the right product
2. Fill in the series number in the search field (do not include the last extensions such as -12 in XLG-150-12)
3. Click the search button
4. Click on the PDF icon to open the specification

5. Click on report

6. Click on the model and scroll down:

7. The DMTBF is shown on the last page of the report in the chapter Reliability test

Tag: DMTBF

LED Drivers are recommended operate at full load as long as it observes the working temperature specified in the datasheet, which means Tc measurement results should be equal to or less than the stated Tc in the datasheet. 5 years warranty complies as long as drivers operate within working Temperature and Tc. Limit as well.

No, they are different. SELV means the LED driver will use a safety isolating transformer with double or reinforced insulation and the output voltage shall not exceed 120Vdc.
This is good for the end product safety certified if the LED driver with SELV output.

Tag: SELV

The definition of SELV was defined in the IEC 60950 standard but it is not defined in the  IEC 62368 standard. This has been replaced with the ES1 Energy sources definition.

The definition of SELV is still applicable to the 61347-2-13 standard. In this standard it is that a LED driver will use a safety isolating transformer with double or reinforced insulation and the output voltage shall not exceed 120Vdc.

In the specification MEAN WELL’s 61347-2-13 certified LED drivers are marked with the SELV symbol in the case that the SELV requirements are fulfilled:

Tag: SELV