Cables, burning

The UL 1685 tray cable burn test was conducted on a cable construction with three different jacketing materials consisting of EVA polymer with 60 wt % Mg(OH)2 (EVA-MH), EVA polymer with 58 wt % Mg(OH)2 and 2wt % nanoclay (EVA-MH-NanoM), and 1 1 EVA PE with 58 wt %... 

FIGURE 26.8 Flame propagation height versus time in UL 1685 tray cable burn test. (Whaley, P.D. et al., Nanocomposite flame retardant performance Laboratory testing methodology, in Proceedings of the 53rd IWCS/Focus International Wire Cable Symposium, 2004, pp. 605-611.)... 

IEC 61034-1 Measurement Of Smoke Density Of Cables Burning Under Defined Conditions—Part 1 Test Apparatus, IEC, Geneva, Switzerland, 2005. 

BS 7622-1 Measurement Of Smoke Density Of Electric Cables Burning Under Defined Conditions— Test Apparatus, BSI British Standards Institution, London, U.K., 1993. 

IEC61034 Part 1 Measurement of smoke density of cables burning under defined conditions. Test apparatus. Part 2 Measurement of smoke density of cables burning under defined conditions. Test procedure and requirements. 

BS7622 Measurement of smoke density of electric cables burning nnder defined... 

While connecting a delta-wound motor through a Y A starter, the metallic shorting links should be removed. Otherwise the starter will have a dead short-circuit at the motor terminal box and may burn the starter, damage the motor terminal box and even line cables. 

Calcium carbonate - emits non-flammable gases and helps to reduce the supply of oxygen lo the burning surfaces. The FRLS cables thus produced would possess the required properties... 

Figure 14 Vertical burning test of EVA-TBPTP cable material. The untreated control sample of EVA can be seen burning.

Martin Hochstadter introduces a three-core power cable that does not become deformed or burn by the high voltage electricity. 

Two further interesting points of note are that on burning silicones form silica which is an insulator, and thus cables insulated with silicone can function after short term exposure in a fire situation silicones are also physiologically inert and this has led to their use in a wide variety of medical applications, including medical implants. 

Samples are normally exposed in a vertical orientation. If samples melt and drip, the heat can be redirected, by means of a system of aluminum foil mirrors, towards a horizontal sample. Many of the materials used for the series of experiments reported here melted excessively, away from the flame. Therefore, vertical burns were impossible for them, without distorting the data. All the materials investigated in the OSU RHR calorimeter, with the exception of the experimental flexible vinyl wire and cable compound, were, thus, exposed horizontally. 

The product used for these calculations was a fire retarded plasticized PVC wire coating material, which does not spread flame or continue burning unless an external source of heat or flame is directed at it. This material was chosen because PVC represents the most common cable... 

Burning of cables and electromotors Drum and barrel reclamation Forest fires Kraft black liquor boilers Cigarette smoking Charcol briquette combustion Various high-temp. 

Fire damage to cable trays can be caused by exposure to flames and heat from spill or pool fires below, falling burning liquids from above, thermal radiation from an adjacent fire, or fire originating among the cables themselves. Cable trays and other grouped cable, wire, and nonmetallic tubing runs should be evaluated to determine the potential for fire exposure where warranted by their size and cost or safety-related importance of their service. 

The amount of air that can be drawn into an enclosure to support combustion will depend on both the size and configuration of ventilation openings in the enclosure. A poorly ventilated fire will create more smoke and byproducts. Any unburnt fuel may also burn outside the enclosure, endangering adjacent areas. A fire in a structure may also cause other fuels to burn such as cables, paint, plastic equipment etc. These will add to the fuel load and to the smoke. 

ASTM D 5424 Standard Test Method for Smoke Obscuration of Insulating Materials Contained in Electrical or Optical Fiber Cables When Burning in a Vertical Cable Tray Configuration... 

ASTM D 5537, Standard Test Method for Heat Release, Flame Spread, Smoke Obscuration, and Mass Foss Testing of Insulating Materials Contained in Electrical or Optical Fiber Cables When Burning in a Vertical Cable Tray Configuration, Annual Book ASTM Standards, American Society for Testing and Materials, West Conshohocken, PA. 

Both by application and by geography, fire safety standards are highly diverse and complex. Some standards tend to focus primarily on preventing ignition and flame spread, while others put additional emphasis on reducing smoke generation and toxic/corrosive by-products from burning wires and cables. 

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