Analysis Of LED Bulb Recall Cases In Recent 5 Years

- Jul 21, 2018-

In the last five years, lighting products have been updated from lamps to controllers to light sources.

In particular, lighting standards, from fluorescent lights to LED lights, have been updated almost entirely.

The light sources involved in exporting to Europe are mainly self-ballast lamps, including self-ballast fluorescent lamps and self-ballast LED lamps.

In the past five years, the mainstream products have been LED self-ballast bulbs, and LED bulbs are the ones that cause more problems in the European market.




Based on the European market lighting product recall information in nearly five years, the LED from the main problems of ballast bulb is analyzed, and the main updates to do a simple introduction to the new standards, aiming to make the LED light bulb manufacturers to understand and follow up the new standard in time, to reduce or prevent products were recalled in the European market.



In 2011, the export volume of LED self-ballast bulbs was low, and there were few recalls. The number of LED self-ballast bulbs soared in 2012, and then declined year by year, reaching the same number in 2015 as in 2011.

The recalls also included big-brand products.

Total number of nearly 50 cases, among them because do not conform to the requirements of the standards, prevent to get an electric shock may click on the damage and recalled in 22 cases, because the creepage distance is not recalled in 16 cases, 5 cases of them are at the same time, the two problems, most recalls defects were focused on the two problems.

Figure 1 shows the number of LED self-ballast bulb recalls in Europe between 2011 and 2015.




(figure 1: specific statistics of the number of LED self-ballast bulb recalls in Europe from November 2011 to 2015)



Involved criteria


There are two kinds of self-ballast bulbs: self-ballast fluorescent lamp and self-ballast LED lamp. The corresponding safety standards of these two products are EN 60968 and EN 62560 respectively.

The two standards are very similar and the architecture is exactly the same. Here, take the safety standard EN 62560 of LED self-ballast lamp as an example.

EN 62560 contains test chapters that start in chapter 5 and end in chapter 18.

The following is a brief introduction based on key terms and troubleshooting terms.


1. Logo, including product nameplate and specification.

It's the identity card of the product.

Therefore, it is necessary to include the necessary feature information of the product.

The standard A1, published in 2015, has been revised.

The symbol for the position of the fuel point is removed (i.e., the point at which the lamp head burns up or down).

Added waterproof symbol, this is a new symbol, it was not there before.

This symbol is now included in several light standards.

The specific shape is as follows:, this sign means "the lamp can only be used in dry environment or protected lamps".

There are recall cases related to this part, which will be described in detail later.


2. Interchangeability. This part contains two parts.

Part is the interchangeability of the lamp, part is the bending moment and quality of the lamp itself.

The interchangeability of the lamp head is the assessment of its size.

Bending moment and quality are the test of the influence of the bulb on the lamp holder in the lamp.

The measure of lamp head size is measured by the gauge of finished lamp head.

A single lamp holder complies with the test lamp holder gauge, to use on the finished lamp, can't guarantee the finished lamp 100% pass the test, for testing, each in the gauge is finished product lamp holder lamp holder gauge, gauge and finished products of different sizes.

But after a single lamp holder meets its own measurement, the chances of the finished lamp passing through will be higher.

Gauges are very precise gauges that are normally only available in laboratories.

Therefore, if this point is unqualified, the factory will be more difficult to change, the size is not easy to grasp.


3. Prevent accidental contact with live parts, which is the part with the most problems in all recall cases.

In short, it means to use standard test to test the possibility of electric shock, but it is more abstract. It is easier to understand when combining with an EK1 decision of German GS certification requirement.

EK1 550-13 resolution gives the following figure:




(figure 2: live parts against accidental contact)


See a picture, very easy to understand, two red circle part is the place that can cause electric shock possibly, so also can know easily, this is the problem that produces in the process that install a lamp or change a lamp.


4. Moistureproof, insulation resistance and dielectric strength, this section is familiar with factory test, insulation resistance and dielectric strength because some lighting products in the process of production is the need to the factory for 100% test.

There is a slight difference between the test method and the type test (the type test conducted in the laboratory).

Some of the problems in the recall cases are found in this section.


5. Mechanical strength is a test to assess the binding strength of all parts of the bulb.

Good combination between each part of the bulb is light bulb production technology more mature in one step, it is not easy to problems and recall cases not found within five years do not meet the requirements of this chapter.

However, unlike traditional incandescent bulbs, self-ballast bulbs usually have more than one part of the lamp body.

Therefore, according to the torque requirement of traditional incandescent lamp, the combination of some parts will be neglected.

Although there have been no recall cases in the European market due to mechanical strength failure, there have been many cases of unqualified products in daily type tests.

The correction will be relatively easy, but it is not easy to understand which parts have mechanical strength requirements in the manufacturing process.

Figure 3 is from the CTL DS 1000 on the IECEE official website.

Mechanical strength requires testing between 1 and 2, between 1 and 3, not just between 1 and 2 in traditional concepts.

Therefore, some self-ballast bulbs will be ignored in the production process of 2 and 3 between the fastening connection, leading to mechanical strength test failure.




(figure 3: mechanical strength)


6. The concept of creepage distance and electrical clearance is difficult for readers who have not been exposed to safety standards.

The creepage distance is the shortest distance between two conductors along the surface of the insulator. The electrical clearance is the shortest distance between two conductors along the air.

This part is related to insulation and protection against electric shock.




(FIG. 4 creepage distance and electrical clearance)


7. Abnormal operation, this part is the new part of A1 in 2015.

It is a test of the safety of a self-ballast light bulb with an undimmed light symbol in accordance with chapter 5.

There is an electronic circuit in the self-ballast bulb. If the circuit design is not suitable for use in the dimmer circuit, the self-ballast bulb cannot be used in the luminaire with the dimmer.

Most of the self-ballast bulbs on the market today are undimmed.

The absence of a recall case in the European market for five years does not mean there is no problem with this part of the recall, as previous versions of the standard did not examine this part.

In the Chinese market, there have been cases of non-dimmable self-ballast fluorescent lamps used in dimming circuits causing dangerous accidents.


8. Photobiosafety testing, which is a new part of A1 in 2015, is not new.

Since the advent of LED lighting products, the test standard EN 62471 for optical biosafety has been born, which was previously used in LED lighting products.

However, in the last five years, the standards of lighting products have been updated to include the requirements of photobiosafety testing as part of the product standards.

Reference standard IEC TR 62778 is based on IEC 62471, it is not the whole content of EN 62471, also can not be replaced by EN 62471, but the product according to their own safety standards for testing, consider this chapter content is enough.

At present, no recall cases that do not meet the requirements of this part have been found, which is also related to the failure of the previous version of the standard to specify what kind of photobiological safety level does not meet the standards.

The new standard sets a limit on the level of light biosafety. The blue light damage of LED self-ballast bulbs can only be RG0 unlimited and RG1 unlimited, not higher.


9. Waterproof test, this part is the additional requirement of A1 in 2015.

This chapter shall be used in conjunction with the logo of chapter 5.

Prior to this, all light source products had basically no waterproofing requirements (except for small power bulbs in EN 60432-1 that can touch water).

But factories often require waterproof testing of their own self-ballast bulbs, which were previously untested because there was no standard, and are now waterproof.

It's just that the waterproof level is only IPX4, unlike the lighting products, which have different waterproof levels.


The above is an introduction to part of the test section, where the non-test section must also mention the definition of LED self-ballast bulb in the definition section of chapter 3.

Some LED self-ballast bulbs have been recalled because they do not meet this definition.

LED the ballast bulb is defined as "light source by the lamp holder of leds and conform to the IEC 60061-1 combined with some other components required for stable work, under the condition of light is not permanent damage cannot be split up or dismantling", the key is after half sentence, many have been recalled from ballast bulb is because they do not conform to the requirements of the half sentence after this definition.



Existing problems and Suggestions


In view of the recall cases in the last 5 years, this paper summarizes the key problems in the case, and lists the specific chapters corresponding to the safety standards. The improvement Suggestions are for the reference of enterprises.


In the nearly 50 cases recalled in the past five years, the main problems mainly focus on the two chapters of creepage distance and anti-shock, which are commonly referred to by enterprises as structural problems.

Electrical aspects such as dielectric strength (commonly known as high voltage testing) unqualified, but less.

Generally, this problem is also caused by insufficient creepage distance or electric clearance, so the main problem is structure.




(table 1: non-conforming items and non-conforming contents)


Only from the above-mentioned reference pictures to see, feel more problems is E27 screw base LED bulbs, but in fact, nearly 50 cases, mostly GU10 shot bubble LED lamp holder (27 cases), E27 screw 15 cases of LED bulbs, most, the rest for the E14, B22, G9 lamp holder, etc.

Reference is made to the picture of the bulb with screw tip because the picture is universal.

It is hoped that the above analysis and Suggestions will be helpful to the enterprises, so that they can notice the points that are prone to problems in the production process and try to eliminate the problems before shipment.

Similarly, enterprises should not take any chances and do not strictly control the quality of products. As a result, extreme cases such as the one in the above table occur.