จำหน่ายเกจวัดแรงดัน Pressure Gauge ทุกยี่ห้อ

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Unlike other cables, fireplace resistant cables should work even when directly uncovered to the hearth to maintain important Life Safety and Fire Fighting tools working: Fire alarms, Emergency Lighting, Emergency Communication, Fire Sprinkler pumps, Fireman’s Lift sub-main, Smoke extraction followers, Smoke dampers, Stair pressurization followers, Emergency Generator circuits etc.
In order to classify electric cables as fire resistant they’re required to bear testing and certification. Perhaps the first common hearth checks on cables had been IEC 331: 1970 and later BS6387:1983 which adopted a gas ribbon burner take a look at to provide a flame in which cables had been positioned.
Since the revision of BS6387 in 1994 there have been 11 enhancements, revisions or new check standards launched by British Standards for use and software of Fire Resistant cables however none of these appear to deal with the core issue that fireside resistant cables where examined to common British and IEC flame check requirements are not required to perform to the identical hearth performance time-temperature profiles as every other construction, system or component in a building. Specifically, the place hearth resistant constructions, methods, partitions, fire doors, fireplace penetrations fire barriers, floors, partitions and so on. are required to be hearth rated by constructing laws, they are examined to the Standard Time Temperature protocol of BS476 elements 20 to 23 (also generally known as ISO834-1, ASNZS1530pt4, EN1363-1 and in America and Canada ASTM E119-75).
These exams are conducted in giant furnaces to duplicate real submit flashover fireplace environments. Interestingly, Fire Resistant cable take a look at standards like BS 6387CWZ, SS299, IEC 60331 BS8343-1 and 2, BS8491 solely require cables to be exposed to a flame in air and to decrease ultimate test temperatures (than required by BS476 pts 20 to 23). Given Fire Resistant cables are likely to be uncovered in the same fireplace, and are wanted to make sure all Life Safety and Fire Fighting methods remain operational, this reality is probably surprising.
Contrastingly in Germany, Belgium, Australia, New Zealand, USA and Canada Fire Resistant cable techniques are required to be examined to the same fire Time Temperature protocol as all other building elements and this is the Standard Time Temperature protocol to BS476pts 20-23, IS0 834-1, EN1363-1 or ASTM E119-75 in USA.
The committees creating the usual drew on the steering given from the International Fire Prevention Congress held in London in July 1903 and the measurements of furnace temperatures made in plenty of hearth tests carried out within the UK, Germany and the United States. The exams were described in a series of “Red Books” issued by the British Fire Prevention Committee after 1903 in addition to those from the German Royal Technical Research Laboratory. The finalization of the ASTM standard was heavily influenced by Professor I.H. Woolson, a Consulting Engineer of the USA National Board of Fire Underwriters and Chairman of the NFPA committee in Fire Resistive Construction who had carried out many exams at Columbia University and Underwriters Laboratories in Chicago. The small time temperature variations between the International ISO 834-1 take a look at as we all know it at present and the America ASTM E119 / NFPA 251 exams likely stemmed from this time.
Image courtesy of MICC Ltd.
The curve as we see it at present (see graph above) has turn into the usual scale for measurement of fire take a look at severity and has proved related for most above ground cellulosic buildings. When elements, structures, parts or systems are tested, the furnace temperatures are controlled to evolve to the curve with a set allowable variance and consideration for initial ambient temperatures. The standards require parts to be tested in full scale and beneath circumstances of help and loading as defined in order to represent as accurately as possible its features in service.
This Standard Time Temperature testing protocol (see graph right) is adopted by virtually all nations around the globe for hearth testing and certification of virtually all constructing constructions, elements, systems and parts with the fascinating exception of fireside resistant cables (exception in USA, Canada, Australia, Germany, Belgium and New Zealand where fireplace resistant cable systems are required to be examined and approved to the Standard Time Temperature protocol, similar to all other building constructions, parts and components).
It is necessary to understand that application standards from BS, IEC, ASNZS, DIN, UL and so on. the place fire resistive cables are specified for use, are only ‘minimum’ requirements. We know today that fires are not all the same and research by Universities, Institutions and Authorities all over the world have recognized that Underground and a few Industrial environments can exhibit very different fire profiles to those in above ground cellulosic buildings. Specifically in confined underground public areas like Road and Rail Tunnels, Underground Shopping centers, Car Parks fireplace temperatures can exhibit a very quick rise time and may reach temperatures properly above these in above floor buildings and in far much less time. In USA at present electrical wiring systems are required by NFPA 502 (Road Tunnels, Bridges and other Limited Access Highways) to withstand fire temperatures up to 1,350 Degrees C for 60 minutes and UK British Standard BS8519:2010 clearly identifies underground public areas such as car parks as “Areas of Special Risk” the place extra stringent test protocols for important electrical cable circuits might need to be considered by designers.
Standard Time Temperature curves (Europe and America) plotted against frequent BS and IEC cable exams.
Of course all underground environments whether highway, rail and pedestrian tunnels, or underground public environments like buying precincts, automobile parks etc. may exhibit different fireplace profiles to these in above ground buildings as a outcome of In these environments the warmth generated by any fireplace cannot escape as easily as it might in above floor buildings thus relying more on heat and smoke extraction tools.
For Metros Road and Rail Tunnels, Hospitals, Health care amenities, Underground public environments like shopping precincts, Very High Rise, Theaters, Public Halls, Government buildings, Airports and so forth. that is particularly important. Evacuation of these public environments is usually gradual even throughout emergencies, and it’s our duty to ensure everyone seems to be given the perfect probability of protected egress during hearth emergencies.
It can additionally be understood today that copper Fire Resistant cables the place put in in galvanized steel conduit can fail prematurely throughout hearth emergency because of a response between the copper conductors and zinc galvanizing contained in the metal conduit. In 2012 United Laboratories (UL®) in America eliminated all certification for Fire Resistive cables the place put in in galvanized steel conduit for this reason:
UL® Quote: “A concern was dropped at our attention related to the performance of these merchandise within the presence of zinc. We validated this discovering. As a result of this, we modified our Guide Information to point that every one conduit and conduit fittings that are available contact with fireplace resistive cables ought to have an interior coating freed from zinc”.
Time temperature profile of tunnel fires using vehicles, HGV trailers with totally different cargo and rail carriages. Graph extract: Haukur Ingason and Anders Lonnermark of the Swedish National Testing and Research Institute who presented the paper at the First International Symposium in Prague 2004: Safe and Reliable Tunnels.
It would appear that some Standards authorities around the globe might must review the present check methodology at present adopted for hearth resistive cable testing and perhaps align the performance of Life Safety and Fire Fighting wiring techniques with that of all the other hearth resistant constructions, components and techniques so that Architects, constructing designers and engineers know that after they want a fireplace ranking that the important wiring system will be equally rated.
For many energy, control, communication and information circuits there might be one expertise obtainable which might meet and surpass all present hearth checks and purposes. It is a solution which is frequently used in demanding public buildings and has been employed reliably for over 80 years. pressure gauge can present a complete and full answer to all the problems associated with the fire safety dangers of recent flexible natural polymer cables.
The metal jacket, magnesium oxide insulation and conductors of MICC cables make positive the cable is effectively fireplace proof. Bare MICC cables don’t have any organic content material so simply can’t propagate flame or generate any smoke. The zero fuel-load of these MICC cables ensures no heat is added to the fireplace and no oxygen is consumed. Being inorganic these MICC cables cannot generate any halogen or toxic gasses at all together with Carbon Monoxide. pressure gauge octa can meet all the current and constructing fire resistance efficiency standards in all countries and are seeing a major increase in use globally.
Many engineers have previously thought of MICC cable know-how to be “old school’ but with the brand new analysis in fireplace efficiency MICC cable system at the moment are proven to have far superior hearth performances than any of the newer more modern flexible hearth resistant cables.
For further info, go to www.temperature-house.com

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