摘要 :
A fiber-optic temperature sensor system has been developed and implemented in the monitoring of the cooking process in pulp production. The sensor system is based on intensity modulation in mechanical multimode fiber connections c...
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A fiber-optic temperature sensor system has been developed and implemented in the monitoring of the cooking process in pulp production. The sensor system is based on intensity modulation in mechanical multimode fiber connections caused by the temperature dependent deflection of a bimetal strip. OTDR technology is used for monitoring the changes in optical power at the sensor points in the network, and a computer system takes care of calibration curves and the power-to-temperature conversion. Fiber segments between the sensor points and the control unit are realized with blown fiber.In this paper, the development and testing of the temperature monitoring system is reported on. Sensor performance, data readout, installation issues and measurement results are discussed. The system is shown to meet the requirements on precision and response time and to be a useful tool for the monitoring of the cooking process.
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摘要 :
A fiber-optic temperature sensor system has been developed and implemented in the monitoring of the cooking process in pulp production. The sensor system is based on intensity modulation in mechanical multimode fiber connections c...
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A fiber-optic temperature sensor system has been developed and implemented in the monitoring of the cooking process in pulp production. The sensor system is based on intensity modulation in mechanical multimode fiber connections caused by the temperature dependent deflection of a bimetal strip. OTDR technology is used for monitoring the changes in optical power at the sensor points in the network, and a computer system takes care of calibration curves and the power-to-temperature conversion. Fiber segments between the sensor points and the control unit are realized with blown fiber.In this paper, the development and testing of the temperature monitoring system is reported on. Sensor performance, data readout, installation issues and measurement results are discussed. The system is shown to meet the requirements on precision and response time and to be a useful tool for the monitoring of the cooking process.
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摘要 :
The major requirement of telecommunications outside network products is to satisfy the performance requisites concerning the various environments in which they are applied. Countries such as Brazil, with large extensions located i...
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The major requirement of telecommunications outside network products is to satisfy the performance requisites concerning the various environments in which they are applied. Countries such as Brazil, with large extensions located in tropical regions, have demanded products designed to specific needs, adjusted technologically to the diverse environments, in order to provide telecommunications network reliability and optimized durability in terms of the cost-benefit ratio. Considering climatic factors such as temperature, relative humidity and atmospheric pollutants, three localities from the five described by Koeppen [1] were selected: Manaus, Fortaleza and Sorocaba. The cables were exposed for 18 months in field. Every three months the samples were removed and submitted to laboratory tests for electric resistivity, tensile test, and visual examination. Salt spray, sulphur dioxide and temperature and humidity assays were carried out in order to simulate the field conditions. In these accelerated ageing assays, the visual and mechanical performance was evaluated. For the environmental characterization, there was a follow-up of parameters of temperature, humidity and pollutants derived from chlorine and sulfur.
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摘要 :
The major requirement of telecommunications outside network products is to satisfy the performance requisites concerning the various environments in which they are applied. Countries such as Brazil, with large extensions located i...
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The major requirement of telecommunications outside network products is to satisfy the performance requisites concerning the various environments in which they are applied. Countries such as Brazil, with large extensions located in tropical regions, have demanded products designed to specific needs, adjusted technologically to the diverse environments, in order to provide telecommunications network reliability and optimized durability in terms of the cost-benefit ratio. Considering climatic factors such as temperature, relative humidity and atmospheric pollutants, three localities from the five described by Koeppen [1] were selected: Manaus, Fortaleza and Sorocaba. The cables were exposed for 18 months in field. Every three months the samples were removed and submitted to laboratory tests for electric resistivity, tensile test, and visual examination. Salt spray, sulphur dioxide and temperature and humidity assays were carried out in order to simulate the field conditions. In these accelerated ageing assays, the visual and mechanical performance was evaluated. For the environmental characterization, there was a follow-up of parameters of temperature, humidity and pollutants derived from chlorine and sulfur.
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Changing environmental interests and new fire safety performance concerns in the wire and cable industry (WCI) have generated studies into the fire hazard and eco-performance of various data and communication cabling system altern...
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Changing environmental interests and new fire safety performance concerns in the wire and cable industry (WCI) have generated studies into the fire hazard and eco-performance of various data and communication cabling system alternatives for computers and local area networks (LAN). To accurately assess the various alternatives, the installed electronic functionality and fire safety performance requirements of the various end-use product options must be equivalent. For high fire performance communication cables (HFP-cables), many existing local and national regulations differentiate between end product performance options and building fire protection needs. High fire-performance, high societal-value based PVC sheathed and perfluoropolymer (PFP) insulated (PVC/PFP) cables can be routed directly in concealed plenum spaces in buildings, while products that do not meet specific high fire performance criteria, such as low-smoke zero-halogen (LSZH/PE) cables or riser-rated cables (CMR or PVC/PE), often must be protected inside other structures that do meet these building fire standards, typically using steel conduit or trunking. However, some low fire performance LAN cables, even fire-protected inside steel conduits, failed to meet the minimum flame spread and smoke criteria that HFP-cables must meet in real-scale cable, fire tests at BRE/FRS and Underwriters Laboratories (when tested as a cable in steel conduit system). Life cycle analysis (LCA) via ISO 14040 methodology is used to evaluate the various cabling alternatives using an appropriate functional unit; a CAT 6 communication LAN cabling system in a typical office building, including cable, steel conduit, couplings and supports as required per building codes for the installation. Key environmental impact assessments for energy consumption, greenhouse gas emissions, and human toxicity are all shown to favor the PVC/PFP systems once the steel conduit is included in the analysis to fire-protect the LSZH/PE or PVC/PE cables. The additional fire safety and installation advantages provided by the PVC/PFP cables more than offsets for the environmental burdens associated with the initial manufacture of just the cable, thereby providing superior overall fire safety, environmental performance, and economic benefits versus LSZH/PE and PVC/PE cables in steel conduits.
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摘要 :
Changing environmental interests and new fire safety performance concerns in the wire and cable industry (WCI) have generated studies into the fire hazard and eco-performance of various data and communication cabling system altern...
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Changing environmental interests and new fire safety performance concerns in the wire and cable industry (WCI) have generated studies into the fire hazard and eco-performance of various data and communication cabling system alternatives for computers and local area networks (LAN). To accurately assess the various alternatives, the installed electronic functionality and fire safety performance requirements of the various end-use product options must be equivalent. For high fire performance communication cables (HFP-cables), many existing local and national regulations differentiate between end product performance options and building fire protection needs. High fire-performance, high societal-value based PVC sheathed and perfluoropolymer (PFP) insulated (PVC/PFP) cables can be routed directly in concealed plenum spaces in buildings, while products that do not meet specific high fire performance criteria, such as low-smoke zero-halogen (LSZH/PE) cables or riser-rated cables (CMR or PVC/PE), often must be protected inside other structures that do meet these building fire standards, typically using steel conduit or trunking. However, some low fire performance LAN cables, even fire-protected inside steel conduits, failed to meet the minimum flame spread and smoke criteria that HFP-cables must meet in real-scale cable, fire tests at BRE/FRS and Underwriters Laboratories (when tested as a cable in steel conduit system). Life cycle analysis (LCA) via ISO 14040 methodology is used to evaluate the various cabling alternatives using an appropriate functional unit; a CAT 6 communication LAN cabling system in a typical office building, including cable, steel conduit, couplings and supports as required per building codes for the installation. Key environmental impact assessments for energy consumption, greenhouse gas emissions, and human toxicity are all shown to favor the PVC/PFP systems once the steel conduit is included in the analysis to fire-protect the LSZH/PE or PVC/PE cables. The additional fire safety and installation advantages provided by the PVC/PFP cables more than offsets for the environmental burdens associated with the initial manufacture of just the cable, thereby providing superior overall fire safety, environmental performance, and economic benefits versus LSZH/PE and PVC/PE cables in steel conduits.
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There has been much recent work in IEEE 802.3an, TIA TR42.7, and other standards groups to quantify channel capacity of unshielded twisted pair (UTP) media. While internal transmission impairments of UTP media such as Return Loss ...
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There has been much recent work in IEEE 802.3an, TIA TR42.7, and other standards groups to quantify channel capacity of unshielded twisted pair (UTP) media. While internal transmission impairments of UTP media such as Return Loss (RL), Near End CrossTalk (NEXT), and Far End CrossTalk (FEXT) are substantially cancelable with digital signal processing (DSP), alien crosstalk (PSANEXT and PSAELFEXT) remains a limiting factor for channel capacity. Many technical contributions have examined cable or connector alien crosstalk but few have quantified the channel alien crosstalk in installed cabling. This paper will present the results of alien crosstalk field testing in three installation sites. The sites utilize different vendor components for Category 6 rated solutions. Testing and analysis associated with this paper can support the standardization efforts in IEEE and TIA.
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摘要 :
There has been much recent work in IEEE 802.3an, TIA TR42.7, and other standards groups to quantify channel capacity of unshielded twisted pair (UTP) media. While internal transmission impairments of UTP media such as Return Loss ...
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There has been much recent work in IEEE 802.3an, TIA TR42.7, and other standards groups to quantify channel capacity of unshielded twisted pair (UTP) media. While internal transmission impairments of UTP media such as Return Loss (RL), Near End CrossTalk (NEXT), and Far End CrossTalk (FEXT) are substantially cancelable with digital signal processing (DSP), alien crosstalk (PSANEXT and PSAELFEXT) remains a limiting factor for channel capacity. Many technical contributions have examined cable or connector alien crosstalk but few have quantified the channel alien crosstalk in installed cabling. This paper will present the results of alien crosstalk field testing in three installation sites. The sites utilize different vendor components for Category 6 rated solutions. Testing and analysis associated with this paper can support the standardization efforts in IEEE and TIA.
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摘要 :
There has been much recent work in IEEE 802.3an, TIA TR42.7, and other standards groups to quantify channel capacity of unshielded twisted pair (UTP) media. While internal transmission impairments of UTP media such as Return Loss ...
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There has been much recent work in IEEE 802.3an, TIA TR42.7, and other standards groups to quantify channel capacity of unshielded twisted pair (UTP) media. While internal transmission impairments of UTP media such as Return Loss (RL), Near End CrossTalk (NEXT), and Far End CrossTalk (FEXT) are substantially cancelable with digital signal processing (DSP), alien crosstalk (PSANEXT and PSAELFEXT) remains a limiting factor for channel capacity. Many technical contributions have examined cable or connector alien crosstalk but few have quantified the channel alien crosstalk in installed cabling. This paper will present the results of alien crosstalk field testing in three installation sites. The sites utilize different vendor components for Category 6 rated solutions. Testing and analysis associated with this paper can support the standardization efforts in IEEE and TIA.
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摘要 :
After years of discussion and debate, a classification system for the reaction-to-fire performance of cables under the European Union Construction Products Directive (EU CPD) has been finalised. National Regulators from each EU me...
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After years of discussion and debate, a classification system for the reaction-to-fire performance of cables under the European Union Construction Products Directive (EU CPD) has been finalised. National Regulators from each EU member state will consider where and how to use the provisions of the new system for the regulation of cable fire safety performance. This presents a new opportunity to improve cable installations within buildings and other construction works in respect of fire safety. The main classification parameters for cable reaction-to-fire performance are flame spread (FS), peak and total heat release (PkHRR, THR), and a fire growth rate index (FIGRA). Additional performance declarations are included for smoke, flaming droplets, and "acidity". Of major significance to the fire safety of communication cable installations, the criteria for Class Bl are set to provide a level of performance that mitigates the potential fire hazard presented by high concentrations of local area network (LAN) cables within hidden building voids. This affords Regulators, Building Consultants, Architects, Insurers and IT system designers an opportunity to take effective risk management action to improve the safety of personnel, reduce fire damage, and minimise exposure to the potentially catastrophic effects and costs associated with business interruption. In total, six performance levels are defined for cables. Two dynamic integrated test methods from the FIPEC study are used to determine the main classification. These same dynamic tests, together with the static "3 metre cube" test are used for smoke declarations, and a static pH/conductivity test on materials is used for "acidity" performance. The classification system therefore has some complexities that must be clearly understood in the marketplace if Europe is to have effective and transparent regulations for cables.
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