1、I. CEPT T/TR*02-03*E 2326434 0030437 5 0 TTR02-03 Page E 1 Recommendation T/TR 02-03 (Innsbruck 1981, revised in Cannes 1983, in Nice 1985 and in Odense 1986) ENVIRONMENTAL CONDITIONS FOR THE EQUIPMENT TO BE INSTALLED IN TELECOMMUNICATION CENTRES Recommendation proposed by Working Group T/TR 12 “Tra
2、nsmission” (TR) Text of the Recommendation revised adopted by Commission “Telecommunications”: “The European Conference of Posts and Telecommunications Administrations, Considering - that the equipment used for telecommunication purposes is generally located in telecommunication centres, - that in v
3、iew of the installation of racks made by different manufacturers, it is necessary to standardize these racks, that the relevant CCITT and CCIR Recommendations do not provide for the necessary standardization, that the CCITT and CCIR do not plan to standardize the environmental conditions in telecomm
4、unication centres, - that the Administrations support the harmonization of telecommunication equipment and systems which could lead to a reduction in the development and production costs for the manufacturers supplying equipment to different countries, O Recommends that members of the CEPT adhere to
5、 the specifications for environmental conditions in telecommunication centres contained in the annex to this Recommendation.” Edition of September 1, 1986 CEPT T/TR*02-03*E = 232bYL4 OOLO4L8 7 Table of contents T/TR 02-03 E Page 3 1. STATIONS AND EQUIPMENT CONCERNED . 4 2. OBJECTIVES 4 3. DEFINITION
6、S 4 4. SPECIFICATIONS 4 4 5 4.1. Limits of temperature and thermal power dissipation of equipment . 4.2. Climatic conditions for telecommunication equipment . 4.3. Biological conditions 9 4.4. Chemically active substances . 9 4.5. Mechanically active substances 10 4.6. Mechanical conditions. . 10 Ed
7、ition of September i, 1986 CEPT T/TR*02-03*E W 232b4L4 OOLO4L 9 W T/TR 02-03 E Page 4 1. STATIONS AND EQUIPMENT CONCERNED This Recommendation applies to stationary equipment to be installed in telecommunication centres which usually have climate-controlling systems and are constructed in such a way
8、that their climatic conditions are not strongly affected by the outdoor conditions. It applies also to certain types of other locations with or without climate-controlling systems. Other specifications deal with equipment instailed at different locations. Note: Conditions in other types of telecommu
9、nication centres or premises will form the subject of other CEPT Recommenda- tions. 2. OBJECTIVES To define the climatic conditions in telecommunication centres. To determine the limits for thermal power dissipation of the equipment. To dene the climatic conditions for transport and warehousing of t
10、he equipment concerned. - To define severities which will have a low probability of being exceeded. All specified values are maxi- mum or limit values. These values may be reached but do not occur permanently. (IEC 721-3-3, 1.) Note: The environmental classification for transport and warehousing wil
11、l be defined at a later date in a single unified document. 3. DEFINITIONS Climate-controlling system (e.g. heating, cooling, forced ventilation, air-conditioning systems) A system that controls or influences climate, acting at least on one climatic parameter in one direction. Heating system A system
12、 that controls or influences climate, increasing the air temperature only, and this can decrease the relative humidity. Cooling system A system that controls or influences climate, decreasing the air temperature only, and this can decrease the absolute humidity. Forced ventilation system A system th
13、at controls or influences climate, conducting outdoor air into the room or expelling air out of the room. Air-conditioning system A system that fully and automatically controls the climatic parameters air temperature and humidity by heating, cooling, humidifying and dehumidifying. 4. SPECIFICATIONS
14、4.1. 4.1.1. Permissible temperature limits for equipment . Limits of temperature and thermal power dissipation of equipment The temperature of the air issuing from the equipment measured at the top of the equipment should not exceed the ambient room temperature by more than 30C. This is to prevent d
15、amage to overhead cables. The maximum temperature of any unprotected external surface of the equipment or any exposed component should not exceed 75C. This is for reasons of safety and applies to all permitted room temperatures. Edition of September 1, 1986 CEPT T/TR*02-03*E = 2326434 0030420 5 = T/
16、TR 02-03 E Page 5 4.1.2. Permissible thermal power dissipation 4.1.2.1. Transmission rack Maximum allowed value for dissipation of a fully equipped rack: Type A rack: 80 W Type B rack: 400 W Racks dissipating up to these powers should only use natural convection. These figures may be exceeded by spe
17、cific types of equipments but the conditions given in section 4.1.1. must be observed. Note I: Some Administrations prefer figures of 60 W and 300 W for type A and B racks, respectively. Note 2: For equipment with standardized racks, values for thermal power dissipation per unit area (Wjm of an equi
18、pment room) are not given because each Administration may choose a different station layout. Note 3: Type A and B racks are defined in Recommendation T/TR 02-01 i. 4.2. 4.2.1. Climatic conditions for telecommunication equipment Measurements of temperature and humidity Measurements should never be ma
19、de either near the vents of air-conditioning systems or near cooling, heating or humidity-controlling installations (at a minimum distance of 1 m and not directly in the airstream) or above or inside technical equipment. The air temperature and the humidity of centres should not be measured near equ
20、ipment. The distance measured horizontally should usually exceed 50 cm. If as a result of the arrangement of the equipment the greater distance cannot be met, measurements should be taken in the centre of the free space that separates the equipment. Nevertheless, the minimum distance should not be s
21、maller than 40 cm. As for the height, measurements should be taken at several heights in relation to the equipment but, in any case, not at a height greater than that of the equipment. In the open air the temperature and humidity should be measured at 2 m above the ground. The temperature should be
22、measured with equipment that absorbs a minimum of thermal radiation. The error of measurement should not exceed hO.5 K. The measurement error of relative humidity should not exceed f 5%. Edition of September 1, 1986 CEPT T/TR*02-03*E = 2326414 0010421 7 T/TR 02-03 E Page 6 4.2.2. Operational conditi
23、ons in telecommunication centres Normal operating conditions. Exceptional operating conditions. Field of 90% frequency of occurrance. - Figure 1 (T/TR 02-03). Climatogram for operation in indoor rooms. (e.g. station, switching centre) The climatogram of Figure 1 (T/TR 02-03) is recommended and gives
24、 the operational conditions for telecommunication equipment in telecommunication equipment rooms and is valid for all Europe up to an altitude of 2000 m. The limits of the climatogram are determined not only by the maximum and minimum values of temperature and relative humidity but also by the maxim
25、um and minimum values of absolute humidity. Such climato- grams take more account of actual ambient conditions: 4.2.2.1. Limits for normal operational conditions These limits include the entire range of pairs of temperature and relative humidity values in which equipment must operate satisfactorily.
26、 Within these limits equipment must meet the requirements set in specifications. Edition of Senter 1, 1986 /“ CEPT T/TR*02-03*E m 232b4L4 0030422 9 m T/TR 02-03 E Page 7 4.2.2.2. Limits for exceptional operational conditions For ranges of values between these limits and those of normal operational c
27、onditions equipment does not necessarily have to satisfy all requirements for normal operational conditions laid down in specifications. In these abnormal conditions the risk of operational disturbances (e.g. intervention of alarms, errors of connection, signalling) increases but the equipment shoul
28、d suffer no irreversible damage, taking into account that the failure rate may increase. Operation in these limits should be limited to a short duration. When the ambient conditions return to normal, the equipment should function satisfactorily. Such exceptional conditions can arise, for example, wh
29、en the air-conditioning plant goes wrong or when repair work is in progress. The limits for normal Operational conditions have been set according to statistical methods, whilst the limits for exceptional operational conditions are based on experimental values. These limits include a field, in which
30、the coupled values of temperature and relative humidity occur during 90% of the time. The limits of this field are based on statistical measurements carried out in European countries with different climatic conditions. Further information on statistical distribution of temperature and humidity is to
31、 be obtained (e.g. max. duration of some extreme climatic conditions). The conditions described by the climatograms do not consider the effect of direct sun radiation and other parameters. Equipment dissipation has been taken into account but the user should consider the total heat load. This means
32、that the administration or the end user is responsible for the limits of the climatogram not being exceeded because of equipment dissipation. To define the environmental conditions to which equipment is subjected, it is necessary to add the following information to that contained in the climato- gra
33、ms: - Rate of change of temperature: O.S“C/min for the climatograms in Figures i (T/TR 02-03) and 3 (T/TR 02-03): 1 .O“C/min for the climatogram in Figure 2 (T/TR 02-03). Note: The values have been averaged over a period of 5 minutes. 4.2.2.3. Limits of 90% distribution 4.2.2.4. Additional condition
34、s - High air pressure: Low air pressure: 106 kPa. 70 kPa (equivalent to a height of 3000 m) which would allow for transportation by air in pressurized holds. 700 W/m2. 600 W/m2 e.g. in the vicinity of room heating systems. 5.0 m/s. - Solar radiation: - Heat radiation conditions: - Movement of the su
35、rrounding air: Notes: 1. More severe conditions may have to be taken into account in particular cases. 2. The values listed are those which will have a low probability of being exceeded, e.g. 0.01 O Environmental parameter Classified IEC-values according to Note 2 Rate of change of temperature I rC/
36、min) I OS*) l.O*) Low air nressure I kPa) I 70 I High air messure I kPa) I 106 I I Solar radiation I W/m2) I 700 I I Heat radiation I w/m*) I 600 I I Movement of surrounding air I (mis) I 5.0 I *) *) For the climatogram in Figure 2 (T/TR 02-03). For the climatograms in Figures 1 (T/TR 02-03) and 3 (
37、T/TR 02-03). CEPT T/TR*02-03*E 232b434 0030423 0 T/TR 02-03 E Page 8 4.2.2.5. Remarks to Figure 1 (T/TR 02-03) Note 1: Relative humidity values of 5 % to 10 % only occur in heated telecommunication centres when outdoor temperature is low and the construction of the building does not provide sufficie
38、nt long term buffer for humidity. These values of relative humidity might cause inconveniences to the equipment (e.g. those using magnetic tapes or disks) as electrostatic discharges with possible loss of information stored in memories or even destruction of high-sensitive electronic com- ponents or
39、 as migration of charged dust particles in high electric field areas as between open relay contacts with possible addition of noise to electric signals, and therefore special precautions need to be taken. Further study on this subject is therefore necessary. Note 2: According to IEC, this climatogra
40、m mainly applies to locations with the following features: - Type of location: Buildings of good thermal insulation or capacity; in warm temperate and warm dry open-air climates also buildings of poor thermal insulation or capacity. Heated and/or cooled. Usually only air temperature is controlled. H
41、eating and/or cooling may be switched off or reduced for part of time, e.g., during nights or week-ends. Examples: Normal living and working spaces, e.g., living rooms, rooms for general use, ofices, shops, workshops for electronic assemblies and other electrotechnical products, telecommunication st
42、ations and switching centres, other working spaces, storage rooms for valuable and sensitive products. - Type of climatic control within the location: 4.2.3. Climatic conditions during transportation For transporting equipment the climatogram of Figure 2 (T/TR 02-03) is recommended. It has been nece
43、ssary to take account of temperatures that are higher than the relevant open-air temperatures due to the “green house effect”. The climatogram for transport conditions shown in Figure 2 (T/TR 02-03) is valid for all Europe and up to an altitude of 2000 m. It is acknowledged that, for some regions of
44、 Europe, less severe conditions can be applied considering the particular open-air climate of the regions concerned. Note: The conditions for transport by air need further study. Edition of September 1, 1986 O O e CEPT T/TR*D2-03*E E 2326414 0030424 2 T/TR 02-03 E Page 9 Figure 2 (T/TR 02-03). Clima
45、togram for transport. (within the entire geographical area of Europe) The ambient conditions defined by the climatogram are those existing outside the package. The packaging should be done in such a way that the ambient affects neither the performance nor the life span of the telecommunication equip
46、ment being transported. It is acknowledged that the equipment should not be exposed to transport conditions for more than 30 days. 4.2.4. Climatic conditions during warehousing For the warehousing of equipment that will be operated in the ambient conditions shown by the climato- gram of Figure i (T/
47、TR 02-03), the climatogram of Figure 3 (T/TR 02-03) is recommended for locations in Europe up to an altitude of 2000 m. Ediiion of February 16. 19x7 CEPT T/TR*02-03*E W 232b414 0030425 4 W T/TR 02-03 E Page 10 10 20 30 40 50 60 70 80 90 100% Figure 3 (T/TR 02-03). Climatogram for warehousing. It is
48、acknowledged that equipment may be warehoused without packaging. 4.3. Biological conditions European telecommunication centres are without risks of biological attacks (Class 3B1 of IEC 721-3-3). 4.4. Chemically active substances 4.4.1. Normal conditions With normal levels of contaminants experienced
49、 in urban areas with industrial activities scattered over the whole area, and/or with heavy trafic the values of normal conditions apply. The severities of these normal conditions should be considered as the requirements for the combined effect of all parameters stated (Class 3C2 of IEC 721-3-3). On locations in the immediate neighbourhood of industrial sources with chemical emissions either special precautions must be taken or the special conditions must be chosen. To avoid uneconomical design at these locations, severe conditions may be selected for particular s
