In the introduction documents for the ETS 300
019-1 and ETS 300 019-2 series it is explicit mentioned that the standards are
related to equipment. Translations from macro climate as defined in the ETS to micro climate, as can
be found inside the equipment, is considered to be the responsibility of the
manufacturer when qualifying components.
The guidance that
you require is found in the introductions to 300 019-1 and 300 019-2. The
introduction to each part is contained in the -0 document e.g. 300 019-1-0
and 300 019-2-0. A short answer is that if no test severity is provided, then a
test is normally not appropriate - either because the condition is considered to
be benign or that no suitable IEC 60068-2 test exists (the notes say which).
For non-weather protected locations 2 categories are given. The 'extended'
category is said to cover all ETSI countries. GSM and GSM based technologies are
increasingly being accepted worldwide e.g. China, Australia, Morocco, the US,
South America etc etc. Is there any ETSI recommendation for environmental
specifications for GSM technologies applied outside of ETSI countries (other
than referring to the IEC documents)?
I have also noted that the classification for weather protected
installations does not have different categories for the the different regions
of Europe. In the case of non-temperature controlled conditions were heat
traps may occur, differences could potentially be significant. Does ETSI have
any standards or recommendations regarding this?
ETSI only covers those conditions in Europe - a similar report (IEC
60721-4-4) which will shortly be issued, covers world-wide conditions - this can
be found on the IEC TC 104 web page or is available from your national
committee. I
n addition, ETSI has a new work item which will extend the scope to extreme
telecomms environmental conditions - this will be a new class (T4.2) and is
currently being formulated.
In
section 4.1, there are these descriptions: "Class 4.1 applies to many ETSI
countries" and "Class 4.1 E covers all ETSI countries."
Q1:
Which countries are included in ETSI countries? Does "all ETSI
countries" include non-European countries? Could you list all the ETSI
countries?
The
new issues of the documents will make this point clear. These are extracts from
the new version of ETSI EN 300 019-1-4:
“Class
4.1E covers all of Europe”.
“NOTE:
The climatic conditions in this class do not correspond to an IEC 60721-3-4
class. In order to define a non-weather protected class covering European
locations where the mean value of the annual extreme values -45°C is chosen as
the low temperature and +45°C as the high temperature for the class 4.1E.”
Climatic
conditions for environmental classes Class 4.1E show solar application of
1120w/m2 but does not advise at what ambient.
For
conformance you need the high temperature in combination with solar radiation.
2. If
they have to be conducted in an ambient of 45Deg C, can you advise which
standards you are referencing?
There
are no other references. The approach of simulation solar radiation by raising
the temperature by 15 degC is based on the ETSI committee technical expertise.
I am currently performing the Class 2.3 Public Transportation Random
Vibration Test.
It seems very severe, the levels are 100x typical ASTM random profiles for
transportation testing. I have two questions:
Are the random vibration levels for Class 2.3 Public
Transportation testing correct? In the latest revision of ETS 300 019-2-2,
V2.1.2 (1999-09), the levels are:
5 to 20 Hz 1 m2/s^3 ASD
20 to 200 Hz - 3 dB/oct
Answer:
The levels in the ETSI document have been checked and found
to be correct. We do not know your referenced ASTM level but we suspect that you
may have made an error in performing the dimension conversion.
The random vibration levels for Class 2.3 Public
Transportation are the same as the other Classes 2.1 Very Careful Transportation
and Class 2.2 Careful Transportation. Is this correct? Given the severity of the
Public Transportation levels, should the the Careful and Very Careful levels be
less.
Answer:
Yes you are correct, the severity of the random vibration is
the same for all transportation classes (the difference in classes are the shock
levels).
Question on ETS 300 019-2-2:
Water test
In
the table 5 on page 12 of ETS300 019-2-2 V2.1.2 (1999-09), regarding the water
test, "Rb:Impacting water, Method 2.2" in "IEC 60068-2-18"
is referred. However there is not a Method Rb 2.2 in the IEC 60068-2-18 (2nd
edition, 2000-10), there is only the Method Rb1.1, 1.2 and 2. So I cannot
specify the test method. I wonder if "Rb 2.2" in the table 5 might be
a miswording for "Rb 1.2"?
Answer:
You
are right. IEC 60068-2-18 has been recently modified (ed. 2; 2000-10). The test
method reported in ETS 300 019-2-2 made reference to
the previous edition (ed. 1; 1989-04+ A1:1993-03). In the second edition the
impacting water tests (Rb) have been renamed due to the fact that the method Rb1
has been cancelled. In practice the 'old' Rb 2.2 test is now called Rb 1.2. Only
the name has changed, the test method and the test severities are the same as
before.
The current version will be updated in the future to reflect the new IEC
standards.
Question
on ETS 300 019-2-2: Humidity test
In
ETS 300 019-2-2:1994, Table 5 (Class 2.3), for the relative humidity test
with the rapid temperature change, the listed test duration is 2 cycles. At
the end of one cycle, IEC states that the temperature limit is between 22C
and 28C, and that the humidity should be between 95% and 100% RH. When
going to the next cycle, it is required to ramp humidity back down to
between 45% and 75% RH, or can the relative humidity be maintained at the
high levels?
Answer:
Yes,
the relative humidities must be maintained at high levels.
I
am wondering if a stabilization period is required between the two cycles.
Answer:
No
stabilization period is required between the two cycles.
Question
on ETS 300 019-2-2
I
am referring to ETS 300 019-2-2 printed May 1994: Environmental conditions and
environmental tests for telecommunications equipment; Part 2-2: Specification of
environmental tests Transportation; Table 5: Test specification T 2.3: Public
Transportation - climatic tests air temperature high under test severity
specifies 85C under condition (10) & (12).
Note
12 says that an additional test of 85C for 6 hr shall be conducted on unpackaged
equipment only. Does this mean since we ship our products packaged we don't test
to 85C but only to 70C? Or does this mean, to ensure product safety inside a box
from solar radiation, all products should be tested unpackaged at 85C?
Answer:
When
the standard transportation is in a package and as such defined in the products
specification, the lower temperature at 70 degC is applicable. If the
package is not protected against solar radiation then the product must be
additionally tested in an unpacked condition for 6-hours in 85 degC test
temperature.
Questions on ETS 300 019-2-3: Climatic tests
For the alternative climatic test methods listed in ETSI 300 019-2-3 on all
classes (class 3.1, 3.2, 3.3, 3.4, 3.5), what is the time period that the
equipment should be tested for at each points S, A, B, C, ....
Answer:
The notes associated with the climatograms require that specimen
(equipment under test) stays at the corner points for a minimum duration of 1h
after temperature stabilization is achieved.
In
ETS 300 019-2-3:1994, Table 4 (Class 3.2), for the high and low air
temperature tests, is it okay to have the systems powered on before reaching
the 16 hour dwells at -5C and 45C/55C?
Answer:
Yes
Do
the climatic test durations take into account the time required for the unit
under test to reach temperature stability? If not, should I add
additional hours before the test duration to ensure that stability is met?
Answer:
Stability need to be obtained before the
start the of the required duration.
Question on ETS 300 019-2-3: "Characteristic Severity" and "Test
Severity"
I
refer to document ETS 300 019-2-3 (Specification for environmental tests.
Stationary use at weatherprotected locations), Page 10, Table 2. Please
could you clarify the categories "Characteristic Severity" and
"Test Severity". I'm not sure why some tests appear to have a
characteristic severity quoted, but there is no need to test to this?
Answer:
The guidance that you require is found in the introductions to 300 019-1 and
300 019-2. The introduction to each part is contained in the -0 document
e.g. 300 019-1-0 and 300 019-2-0.
The characteristic
severity is the conditions that can be expected to be found at the telecomms
location described by the class using IEC 60721-3 conditions. This is fully
described in the part 1 series of 300 019. The Part 2 documents then describe
appropriate tests where necessary. If no test is given in the test severity
column then the condition is either considered to be benign or there is no
appropriate IEC 60068-2 test available (the notes say which).
Question on ETS 300 019-2-4: Vibration/shock test loads specified
The units for the load levels (acceleration) specified in table 3 are give in
m/s2. Please confirm the correctness of the units since the specified loads seem
to be very low (e.g. sine load 0.4 g only). Units in g, resulting in 9.81 times
higher loads, would be expected instead.
Answer:
The committee considers that the standard is correct and reflects the
real environmental conditions experienced in this class.
Question on ETS 300 019-2-4: Temperature tests
We have to develop an equipment according to the 300 019-2-4 T4.1E standard.
The temperature range asked by the product management is (-45°C ;+45°C) with
1120W/m². Our product is equipped with a solar-shield.
I have a question on the temperature tests :
- low temperatures : -45°C or -55°C?
- high temperatures : +45°C OR +45°C with solar load?
Answer:
Please see notes 1 & 2 in the standard – If the
equipment is protected from heat irradiation and solar gain (i.e. You have
fitted a solar shield and have adequate ventilation) you need to test at -45°C
and +45°C (not +60°C which we assume you mean).
Question on ETS 300 019-2-4: Damp
heat cyclic tests
In
table 2: Test Spec T 4.1E : Stationary use in non-weather protected
locations, the damp heat cyclic test defines parameters of +30C, 90-100%RH in
accordance with IEC 60068-2-30.
Does
this 30C define the maximum temp for this test (which in the IEC graph for
variant 1 is +40 or +55), or does it define the temperature from which the cycle
should start?
Answer:
Yes
the 30 degC is maximum temperature as explained in the related note.
Question on ETS 300 119-3 and ETS 300 119-4: Weight measures
In point 5.1 and 5.2 of ETS 300 119-3 it is specified that the Weight must be
expressed in SI unit force in N (more properly in kN). On the other hand, in
point 6.1 of ETS 300 119-4 it is specified that the Weight shall be expressed in
Kg. What is correct, N or Kg?
Answer:
Both are correct:
In ETS 300119-3 point 5 the subject is "floor loading" and this must
be given in kN/m2, as it refers to the force that the
racks make towards the floor.
In 6.1 of ETS 300 119-4 the subject is the weight of a subrack, in the
meaning that the people carrying out the installation shall be able to handle
it, and this must be given in Kg.
Question on ETS 300 753:
Acoustic noise
In the standard is defined the declared A-weighted sound power
specification and the high temperature A-weighted sound power one. We consider
the case of telecommunication base stations in which the cooling fans generate
environmental acoustic noise.
Is it so that the acoustic noise should be
specified only according to the LwAd and not yet according to HLwad at all?
Answer:
ETSI
chose not to set high limits because this gets into the realm of health and
safety. That is, while not very likely, some types of outdoor
communications equipment can potentially be a source of hearing damage if
someone is in close proximity to it for a long time (hours). So, at
the time the document was developed, there was a worry that ETSI limits for high
levels would come into conflict with national or regional health and safety
limits. Since, these values are not the same everywhere, this becomes a
very messy issue.
When HLwad will be updated to be relevant, will the certain limits be
defined as presented for LwAd?
Answer:
EE1 thinks that the rationale noted above will not change and ETSI will remain
focused only on the lower level LwAd limits.
When the recommendations for outdoor solutions will be defined as
requirements? What about some specifications for source directionality?
Answer:
Since the original document was issued, there has been no work to address the
outdoor questions. The information on outdoor noise was put in as an
attempt to provide a framework for outdoor problems. Setting limits
for the outdoor noise is inherently much more difficult than for indoors.
It was hoped that interested parties would come back to ETSI with new
information/data/suggestions, and that this would renew the discussion. To
the best of our knowledge, there has been very little feedback to date so no
work has begun.
Question on ETS 300 753: Reading measurements
In
relation to ETS 300 753 spec (Acoustic Noise Emitted by Telecommunications
Equipment) the values in Table 1 page 11 give LwAd for 3.1 (Telecommunication
equipment room unattended) as 7.5 bels. My understanding was that LwAd which is
the declared A-weighted sound power level was measured in Watts.
I
am trying to compare this to another spec (NEBS/Bellcore) which measures the
equivalent reading as an SPL of 83dB. How to I convert LwAd (Power) to a Sound
Pressure Level (SPL) reading.
Answer:
It
is not possible to convert by calculation. Measurements need to be undertaken.
See ECMA TR/27: “Method for prediction of installation noise levels” for
further information.
Question on ETS 300 753: Night-time simulation
Our
cooling devices are used in Base Transceiver Stations all over the world, and a
lot of our customers are requesting us to meet the ETS 300 753 standard for
Acoustic noise emitted by telecommunications equipment.
We
have for years been specialising in combined cooling units where a
"passive" cooling device such as heat exchangers can remove the heat
load up to a certain temperature whereafter the active cooling (air-conditioner)
together with the passive is in function up to the specified maximum
temperature.
Our
question is relating to point A.3.2 in Annex A regarding Night-time simulation.
If there's no need for active cooling at the temperature limit specified in the
standard, will it then be necessary to force the air-conditioner to be
functional?
Answer:
Yes, the cooling system needs to be active and all noise emitting devices also
need to be active.