According to the 2013-2017 Chinese intelligent building industry development prospects and investment strategy analysis report, according to the intelligent building industry market in China for the first time in 2005 reached 20 billion yuan, or more than 20% a year growth development, the size of the market in 2012 reached 86.1 billion yuan.From the point of view, the development of intelligent building in China in recent years is very fast, which shows that intelligent buildings is a trend in the development of the future construction.
Since is a building, you will use a lot of communication cables.But as the nervous system in the intelligent building integrated wiring system, is a key part of intelligent building and infrastructure, it has to do with the planning and design of construction projects, construction installation and maintenance to use has a very close relationship.It's like building a information highway, people on this channel convenient, fast and effectively communicate and communication.Inside the intelligent building integrated wiring system, as it were, communications, computers and all kinds of facilities and equipment are interconnected to form the whole form a complete set of complete, to meet the requirements of highly intelligent.
But now we have to consider a problem: fire.Because the building in case of fire, the cable release of heat and gas will become the major safety concerns.In recent years the domestic several big fire accident, many is because the victim cannot escape, cable combustion emit toxic acid gases, and burning release a lot of heat, smoke, victims caused by breathing difficulties, led to the tragedy.Therefore, we in the integrated wiring system cables when the choice, besides should consider performance, fire prevention and environmental protection is also particularly important reference factor.
Our country promulgated in 2007 the integrated wiring project design specification GB50311-2007 for the first time the introduction of cable fire prevention and environmental protection level, the guidelines recommend domestic user selected according to different situations in different levels of fire protection or environmental protection cable.
The current communication cable sheath material first in the domestic market is divided into three types:
Integrated wiring is one of the key links of information network system, in order to ensure information network system of high speed, stable operation, choose high quality, high performance of the cable is particularly important.
The cable should be selected according to the requirement of the system, technical performance, investment estimate factors such as comprehensive consideration, but in a wiring system shall, first of all, determine the type of is to use the cable and wiring structure (not shielded cables, shielded cables, fiber optic cable, or several mix).Cables are usually use wire with insulation layer and use a layer or multilayer plastic skin.And cables are usually composed of 2 to 3600 line to.Multi-cores cable wiring system is usually used in the trunk, they are suitable for use in voice and low rate of data transmission.The cable in the trunk and level (hub to desktop) wiring system of the application of the maximum length in detailed instructions are included in the latest GB50311-2007.It is important to note these maximum length limit applies to all media.They are not considered due to the network using the cable type and protocol types of different and the influence of the performance differences.In fact, the biggest cable length will depend on the application of the system, the network type and the quality of the cable.
Integrated wiring system cable selection method
1, the common type (PVC);
Type 2, low smoke zero halogen (LSZH/LS0H);
Type 3, refractory (fireresistant).Integrated wiring cable fire or environmental level should choose according to the actual situation of the comprehensive thinking:
Overhead floor or ceiling
Building overhead floor or ceiling for PVC wiring duct/pipe and install the air conditioning ventilation system, appropriate USES flame retardant grade in overhead floor or ceiling (CMP or OFNP cable;If building overhead floor or the ceiling using metal trough/tube or flame-retardant PVC wiring duct/pipe, can be used at the fire rating (CM / / CMR/CMP or OFN/OFNR/OFNP) cables.For a building with environmental protection requirements such as relatively dense crowd occasions (airport, subway, railway stations, hospitals, convention and exhibition center, etc.), design of integrated wiring project selection fit levels of LSZH cable, at the same time should adopt fire prevention function of the metal trough/tube or flame retardant PVC wiring duct/pipe.
The vertical shaft
Buildings in the vertical shaft for the PVC trough line (pipe), vertical shaft should be adopt vertical (CMR or OFNR) above grade cable or optical cable;In the vertical shaft for metal trough/tube (or flame retardant PVC wiring duct/pipe), vertical shaft can be used in randomly fire rating (CM/CMR/CMP or OFN/OFNR/OFNP) cables.
Comprehensive the above analysis, in addition to the designers to consider in the design of the cable technical performance indicators and the way of linear factors, construction installation personnel must also ensure that organization construction according to design requirements and specifications, inspection personnel must be in strict accordance with the specifications and design for testing and acceptance, in order to ensure that information network of high quality, high performance operation.If do not have in the intelligent building integrated wiring system, all kinds of facilities and equipment and normal operation of the transmission medium and because there was no information, intelligent also difficult to achieve.Cable selection and system also become the elements of cannot be ignored, in here, we also remind you that in addition to consider comprehensive wiring system cable performance, fire prevention and environmental protection should also be taken into consideration, promote the building of safety index.