Amendment 2 - LED modules for general lighting - Performance requirements

Amendement 2 - Modules de LED pour éclairage général - Exigences de performance

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IEC 62717
Edition 1.0 2019-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
A MENDMENT 2
AM ENDEMENT 2
LED modules for general lighting – Performance requirements
Modules de LED pour éclairage général – Exigences de performance
IEC 62717:2014-12/AMD2:2019-01(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 62717
Edition 1.0 2019-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
A MENDMENT 2
AM ENDEMENT 2
LED modules for general lighting – Performance requirements
Modules de LED pour éclairage général – Exigences de performance
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.140.99 ISBN 978-2-8322-6406-5

Warning! Make sure that you obtained this publication from an authorized distributor.

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® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 62717:2014/AMD2:2019
© IEC 2019
FOREWORD
This amendment has been prepared by subcommittee 34A: Lamps, of IEC technical
committee 34: Lamps and related equipment.
The text of this amendment is based on the following documents:
FDIS Report on voting
34A/2121/FDIS 34A/2127/RVD

Full information on the voting for the approval of this amendment can be found in the report

on voting indicated in the above table.

The committee has decided that the contents of this amendment and the base publication will

remain unchanged until the stability date indicated on the IEC website under

"http://webstore.iec.ch" in the data related to the specific publication. At this date, the

publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates

that it contains colours which are considered to be useful for the correct

understanding of its contents. Users should therefore print this document using a

colour printer.
_____________
2 Normative references
Delete the reference to CIE 121:1996 and the reference to IES LM-80, added by
Amendment 1.:
Add the following new references:
CIE S 025/E:2015, Test Method for LED Lamps, LED Luminaires and LED Modules

ANSI/IES LM-80-15, Approved Method: Measuring Luminous Flux and Color Maintenance of

LED Packages, Arrays and Modules
3 Terms and definitions

Replace terminological entries 3.5, 3.7, 3.11, 3.12 and 3.13 with the following new entries:

---------------------- Page: 4 ----------------------
IEC 62717:2014/AMD2:2019 – 3 –
© IEC 2019
3.5
flux degraded LED product

operating LED product that emits an amount of luminous flux less than the luminous flux

relating to the required luminous flux maintenance factor x

Note 1 to entry: For illustration of gradual depreciation mode, causing a flux degraded product, see Figure C.1.

Note 2 to entry: In general, LED products include LED lamps, LED modules and LED luminaires although this

term can be used with any LED based lighting product.
3.7
median useful life

length of operating time during which a total of 50 % (B ) of a population

of operating LED modules of the same type have flux degraded to the luminous flux

maintenance factor x
Note 1 to entry: The median useful life includes operating LED modules only.

Note 2 to entry: By convention, the expression “life of LED modules” without any modifiers is understood to mean

the median useful life.
3.11
combined failure value
CFV

percentage of LED modules or LED luminaires having either flux degraded or abruptly failed at

median useful life L
Note 1 to entry: CFV = 50 % + 0,5 × AFV.
EXAMPLE Given AFV = 15 %, then CFV = 50 % + 0,5 × 15 % = 57,5 %
Note 2 to entry: This note applies to the French language only.
3.12
combined life
M F
x y

length of time during which y % (F ) of a population of initially operating LED

lamps of the same type have either flux degraded to the luminous flux maintenance factor x or

abruptly failed

Note 1 to entry: The combined life (of LED lamps) includes operating and non-operating LED lamps.

3.13
median combined life

length of time during which 50 % (F ) of a population of initially operating

LED lamps of the same type have either flux degraded or abruptly failed

Note 1 to entry: The median combined life (of LED lamps) includes operating and non-operating LED lamps.

Add, at the end of Clause 3, the following new terminological entry:
3.22
useful life
L B
x y

length of time until at maximum a percentage y of a population of operating

LED modules of the same type have degraded to the luminous flux maintenance factor x

Note 1 to entry: The useful life includes operating LED modules only.

Note 2 to entry: Typically median useful life values L are provided (see definition 3.7).

---------------------- Page: 5 ----------------------
– 4 – IEC 62717:2014/AMD2:2019
© IEC 2019
4 Marking
4.1 Mandatory marking
Table 1
Replace item c) and item m) as follows:
c) Rated median useful life L (h) and the related luminous flux
– x x
maintenance x
m) void – – –
Add, after table footnote 5 the following new table footnote 6:

6 The rated useful life L B (in hours) and the associated luminous flux maintenance factor x and percentage y

x y
can optionally be on the product datasheets, leaflets or website.
4.2 Additional marking

Replace, in the first and second paragraphs, "estimated life time" with "median useful life".

Table 2
Replace the existing title with the following new title:
Table 2 – LED module median useful life information

Replace, in the first column, second row, "Rated life time (h)" with "Median useful life L (h)",

as follows:
a a a
Median useful life L (h) XX XXX XX XXX XX XXX
6 Test conditions
6.1 General test conditions
Replace the fourth paragraph with the following new paragraph:
Testing duration is 25 % of rated median useful life with a maximum of 6 000 h.

In the fifth paragraph, added by Amendment 1, replace "IES LM-80" with "ANSI/IES LM-80-

15".
8 Light output
8.3 Luminous efficacy
Delete the content of Subclause 8.3 and replace with "Void".
9 Chromaticity coordinates, correlated colour temperature (CCT) and colour
rendering
9.3 Color rendering index (CRI)
Replace the existing text with the following new text:
---------------------- Page: 6 ----------------------
IEC 62717:2014/AMD2:2019 – 5 –
© IEC 2019
The initial colour rendering index (CRI) of a LED module is measured.
Compliance:

For all tested LED modules in a sample the measured CRI shall not be lower than 3 points

from the rated CRI (see Table 1).
10 LED module life
10.2 Lumen maintenance
Replace Subclause 10.2 including its title, with the following new subclause:
10.2 Luminous flux maintenance

The rated luminous flux maintenance factor may vary depending on the application of the LED

module. Dedicated information on the chosen percentage should be provided by the
manufacturer.

NOTE 1 As the typical life of a LED module is (very) long, it is within the scope of this standard regarded

impractical and time consuming to measure the actual luminous flux reduction over life (e.g. L ). For that reason

this standard relies on test results to determine the expected lumen maintenance code of any LED module.

NOTE 2 The actual luminous flux maintenance of LED modules can differ considerably per type and per

manufacturer. It is not possible to express the luminous flux maintenance of all LEDs in simple mathematical

relations. A fast initial decrease in luminous flux does not automatically imply that a particular LED will not make its

rated life.

NOTE 3 Other methods providing more advanced insight in luminous flux depreciation over LED module life are

under consideration.

This standard has opted for “lumen maintenance codes” (see Figure 2) that cover the initial

decrease in luminous flux until an operational time as stated in 6.1. There are three codes

which define luminous flux maintenance in percent of the initial luminous flux (see Table 6).

Table 6 – Lumen maintenance code at an operational time as stated in 6.1
Luminous flux maintenance Code
≥ 90 9
≥ 80 8
≥ 70 7

The initial luminous flux shall be measured. The measurement is repeated at an operational

time as stated in 6.1. The initial luminous flux value is normalized to 100 %; it is used as the

first data point for determining LED module life. The measured luminous flux value at an

operational time as stated in 6.1 shall be expressed as maintained value (= percentage of the

initial value).

It is recommended to measure the luminous flux at 1 000 h intervals (expressed as a

percentage of the initial value) for a total equal to an operational time as stated in 6.1.

NOTE 4 This will give an additional insight as to the reliability of the measured values, but assigning a code does

not imply a prediction of achievable life time. LED modules with a higher code could be better or worse than LED

modules with a lower code.

For marking of the luminous flux maintenance factor x and the lumen maintenance codes, see

Table 1.
---------------------- Page: 7 ----------------------
– 6 – IEC 62717:2014/AMD2:2019
© IEC 2019

Compliance at 25 % of rated median useful life L with a maximum of 6 000 h test duration:

For compliance of family members, refer to 6.2.3.

An individual LED module is considered as having passed the test when the following criteria

have been met.

1) The measured luminous flux value at 25 % of the rated median useful life (with a maximum

duration of 6 000 h) shall not be less than the initial luminous flux, multiplied by the rated

luminous flux maintenance factor x.

2) The calculated luminous flux maintenance (being the ratio of the measured maintained

and initial luminous flux) shall correspond with the “lumen maintenance code” as declared

by the manufacturer or responsible vendor.

Given a sample of n LED modules according to Table 7 being subjected to the 25 % of rated

median useful life test with a maximum of 6 000 h, it is deemed as having passed the test, if

at the end of the test, at least 90 % of the LED modules have passed.
(2)
(1)
100
Code 9
Code 8
Code 7
Luminous
flux 70
as % of initial
(3)
luminous flux
1 000 6 000 Rated life (h)
IEC
Key
(1) Initial luminous flux
(2) Measured luminous flux value at an operational time as stated in 6.1
(3) Lower limit line: claimed flux decrease over rated life L
NOTE The figure is given for illustrative purposes only.
Figure 2 – Luminous flux depreciation over test time
10.3 Endurance tests
10.3.3 Supply switching test
Replace the first paragraph with the following new text:

At test voltage, current or power, the LED module shall be switched on and off for 30 s each.

The cycling shall be repeated for a number equal to half the rated median useful life L in

hours (example: 10 000 cycles if rated median useful life is 20 000 h).
---------------------- Page: 8 ----------------------
IEC 62717:2014/AMD2:2019 – 7 –
© IEC 2019
10.3.4 Accelerated operation in life test

Replace the third paragraph, starting with "At the end of this period…", with the following new

text:

At the end of this period and being stabilized at t , all the LED modules have an allowed

p,rated

decrease of light output at the end of the test of maximum 20 % compared to the initial value,

for at least 15 min.
Replace the note with with the following new note:
NOTE This test is to check for abrupt failures.
11 Verification
Table 7
Delete the line "8.3 Efficacy".
---------------------- Page: 9 ----------------------
– 8 – IEC 62717:2014/AMD2:2019
© IEC 2019
Replace Annex A with the following new Annex A:
Annex A
(normative)
Method of measuring LED module characteristics
A.1 General

Unless otherwise specified in Clause A.1, for general conditions of photometric and

colorimetric measurements CIE S 025/E:2015, Clauses 4 and 5 apply.

Unless otherwise declared, LED modules do not require any ageing prior to testing. An ageing

period of up to 1 000 h may be specified by the manufacturer.

Unless otherwise specified, all measurements shall be made in a draught free room at a

relative humidity of 65 % maximum.

The temperature at the t -point shall be set at the recommended maximum LED module

operating temperature value, t for the measurements. If not accessible, the
p rated

manufacturer shall indicate a temperature monitoring point. If heat sinks are needed for the

correct operating of the LED module and the LED module does not have a heat sink, a

suitable temperature controlled heat sink may be used.

Interpolation techniques for photometric and colorimetric data at t may also be applied (see

also CIE S 025/E:2015, Annex C for information). Measurements may be performed at

different temperatures. For this, the relation between the two temperatures (t and a

p,rated

different t within the range of the manufacturer's provided data) and the measured

characteristic shall be established beforehand in an unambiguous manner by data provided by

the LED module manufacturer. In case of doubt the reference measurement is performed at

t . Depending on the type of control circuit the LED module manufacturer is using, the t

p,rated p

measurement shall be done at the most onerous condition of operation. The value of t

p,rated
shall be reported in Clause 4.

The manufacturer shall provide, on request, information on the method used to reproduce the

claimed characteristics declared at t -point.

For surface temperature measurement, equipment as specified in informative Annex H may be

used.

Independent LED modules that incorporate heat sinks are operated in free air and measured

at a temperature of 25 °C with a tolerance of ±1,2 °C.

Maintenance (10.2) and supply switching (10.3.3) operation shall be conducted in the

temperature interval (t – 5 K ≤ t ≤ t ) at a rated maximum ambient temperature
p_rated p p_rated

specified by the manufacturer, with a tolerance of ( K). In case there is no rated maximum

ambient temperature, the ambient temperature range (20 °C ≤ t ≤ 25 °C) shall be used.

amb

For the supply switching test, the temperature requirement is applicable only during the ON

time. The value of t shall not be exceeded. An appropriate heat sink or additional

p,rated

heating may need to be applied to obtain the correct t value. For testing purposes, the t

p,rated p

-point shall be easily accessible. Even if the location is different for t and t , the value of t

p c c
shall not be exceeded.
---------------------- Page: 10 ----------------------
IEC 62717:2014/AMD2:2019 – 9 –
© IEC 2019
A.2 Electrical characteristics

The test voltage, current or power shall be the rated voltage, current or power. In the case of

a range, measurements shall be carried out at the input value corresponding to the most

adverse effect to the temperature of the LED module.
A.3 Photometric characteristics
A.3.1 General

Description and requirements for photometric and colorimetric measurement equipment are

provided in CIE S 025/E:2015, 4.5.
A.3.2 Test voltage, current or power

For electrical test conditions and electrical equipment see CIE S 025/E:2015, 4.3.

A.3.3 Luminous flux
Luminous flux shall be measured in accordance with CIE S 025/E:2015, Clause 6.
A.3.4 Luminous intensity distribution

Luminous intensity distribution shall be measured in accordance with CIE S 025/E:2015,

Clause 6. For directional LED modules, beam angle and peak intensity are determined

according IEC TR 61341.

Luminous intensity distribution data shall be available for all variations of the LED module and

any optical attachments or accessories specified for use with the LED module.

Luminous intensity distribution data shall be provided for the LED module in accordance with

an established international or regional format.

NOTE Information about file formats can be found in IEC 62722-1:2014, Annex A, for informative (not normative)

purposes.
A.3.5 Colour characteristics

Colour quantities shall be measured in accordance with CIE S 025/E:2015, Clause 7.

The value of the colorimetric quantities of LED modules may be angularly dependent.

Spatially averaged chromaticity coordinates shall be used, unless otherwise specified by the

manufacturer.
---------------------- Page: 11 ----------------------
– 10 – IEC 62717:2014/AMD2:2019
© IEC 2019
Annex B
B.2 Binning procedure of white colour LEDs
Delete the contents of Clause B.2 and replace with "Void".
---------------------- Page: 12 ----------------------
IEC 62717:2014/AMD2:2019 – 11 –
© IEC 2019
Replace Annex C with the following new Annex C:
Annex C
(informative)
Explanation of recommended LED product lifetime metrics
C.1 General

Life of an individual LED module is the length of time during which an individual LED module

provides at least percentage x of the initial luminous flux, under standard test conditions. The

end of life of an individual LED module can be reached by either flux degradation or abrupt

failure (operating and inoperative LED modules).

NOTE For better readability, the term "LED product" is used and is considered as "LED based lighting product".

An abrupt failure of a LED module is a failure of the entire module and not necessarily a

failure of single LED packages. A failure of single LED packages in a LED module with

multiple packages usually contributes to overall gradual light output degradation of that LED

module. At the time the light output of the LED module becomes less than claimed percentage

x it is considered a flux degraded LED module. Figure C.1 gives an illustration of gradual and

abrupt failure modes, causing a flux degraded LED product and abrupt failure, in a luminaire

comprised of a single LED module.
New LED luminaire Gradual* Abrupt failure
(e.g with 1 LED module)
LED module Lumen Lumen Complete failure
with multiple depreciation* depreciation*
LED packages of LED packages and abrupt
failures of some
LED packages
Light output 100 % Light output 1 % to 99 % Light output 0 %
IEC

* Overall luminous flux depreciation includes also optical parts degradation of the LED

luminaire; gradual luminous flux depreciation below x percent leads to a flux degraded LED product.

Figure C.1 – Light output over life of a LED-based luminaire
comprised of a single LED module
---------------------- Page: 13 ----------------------
– 12 – IEC 62717:2014/AMD2:2019
© IEC 2019

Life time of LED products can be far more than what practically can be verified with testing.

Furthermore the decrease in light output differs per manufacturer making general prediction

methods difficult. This standard has opted for lumen maintenance codes that cover the

decrease in luminous flux until an operational time as stated in 6.1. Due to this limited test

time the claimed life of a LED product cannot be confirmed nor rejected. The recommended

metrics for specifying LED product life is explained below and provides the background for the

pass/fail criterion of the lifetime test as in 10.2.

It is recommended for LED products to specify the luminous flux maintenance apart from the

abrupt failures in a standardised way giving more insight in light output behaviour.

C.2 Life time specification for gradual light output degradation

The length of time until a percentage y of a population of operating LED modules reaches

B life”) and

gradual light output degradation of a percentage x is called the useful life (or “L

x y
expressed in general as L B .
x y

LED products with light output lower than the required luminous flux maintenance factor x are

called flux degraded, because they produce less light but still operate. “L B life” is the age

x 10

at which 10 % of products have flux degraded. The age at which 50 % of the LED modules are

flux degraded, the “L B life”, is called "median useful life" and expressed as L . The

x 50 x

population includes operating LED modules only; non-operative modules are excluded.

Example: L B = L B is understood as the length of time during which 10 % (B ) of a

x y 70 10 10

population of operating LED modules of the same type have flux degraded to less than 70 %

of their initial luminous flux.
100 %
Projection curve individual LED product
φ rel
50 % percentile
Probability density function
x %
(e.g. 70 %
Lumen maintenance curve,
B expresses percentile gradual light output degradation
connecting the B points
(B is 50 % percentile or median)
0 2 4 6 L B L B L B
x 10 x 50 x 90
t (kh)
Operating hours
10 % percentile
Measured data
(time at which F(t) = 0,1)
IEC
Figure C.2 – Life time specification for gradual light output degradation

The shape of the probability density function pdf and the shape of the projection curve in

Figure C.2 are for illustration purposes only. The probability density function can be Weibull,

lognormal, exponential or normal depending on the measured data and selected projection

method.

In reliability terms, the failure function F(t) or cumulative distribution function CDF(t) can be

used to describe flux degraded LED products. F(t) or CDF(t) gives the failure percentile as

function of time. This is mathematically expressed as follows:
---------------------- Page: 14 ----------------------
IEC 62717:2014/AMD2:2019 – 13 –
© IEC 2019
() () ()
F t = CDF t = pdf t dt

By definition F(t→∞) is equal to 1 (100 %). In other words the total area below the pdf curve

from t = 0 to t →∞ is 1, meaning the whole population fails eventually.
Explanation of B:

Example: Considering a luminous flux maintenance factor x of 70 %, 10 % of the population

failed at time L B indicated by the grey area in Figure C.2, mathematically expressed as

70 10
follows:
70 10
F L B CDF L B pdf t dt 0,1→ 10 %
( ) ( ) ()
70 10 70 10 70
The reliability function equals R(t) = 1 − F(t), expressing reliability.
C.3 Lifetime specification for abrupt light output degradation

The length of time until a percentage y of a population of LED modules reaches abrupt light

output degradation of a percentage y is called the time to abrupt failure and expressed as

C .The time to abrupt failure (or “C life”) expresses the age at which a given percentage, y, of

LED modules have failed abruptly. See Figure C.3.

Example: C is understood as the length of time during which 10 % of the population of

initially operating LED modules of the same type fail to produce any luminous flux at all.

10 % failures
100 %
R(t)
pdf
50 %
abrupt
C C C t (kh)
10 50 90
Operating hours
IEC
Figure C.3 – Reliability curve R for abrupt light output degradation
abrupt
50 % failures
90 % failures
= = =
---------------------- Page: 15 ----------------------
– 14 – IEC 62717:2014/AMD2:2019
© IEC 2019
C.4 Combined gradual and abrupt light output degradation

The length of time until a percentage y of a population of LED lamps reaches combined

gradual and abrupt light output degradation, meaning the LED lamps have either flux

degraded, no longer producing at least x % of their initial luminous flux, or abruptly failed, is

called the LED lamp life (or “M F life”) and expressed in general as M F .
x y x y

For example: M F = L F is understood as the length of time during which 10 % (F ) of a

x y 70 10 10

population of LED lamps of the same type have failed by either parametric or abrupt failure

modes (producing less than 70 % of their initial luminous flux or no luminous flux).

The “M F life”, is defined as the median LED lamp life and is called M .
x 50 x

The combined gradual and abrupt light output degradation can be constructed from the above

two specifications via reliability curves in three steps.

Step 1: Construct the reliability curve for flux degraded LED products due to gradual light

output degradation (see Figure C.4).

Step 2: Construct the reliability curve for abrupt light output degradation (see Figure C.3). The

reliability curve in Figure C.3 expresses also the survival of the LED products.

Step 3: Construct the reliability curve for combined degradation as the product of the gradual

light output degradation and abrupt light output degradation (see Figure C.5).
10 % degraded
100 %
R(t)
pdf
50 %
0
R at L
x
gradual
L B L B L B
t (kh)
x 10 x 50 x 90
Operating hours
IEC
Figure C.4 – Reliability curve R for gradual light output degradation
gradual
50 % degraded
90 % degraded
---------------------- Page: 16 ----------------------
IEC
...

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