Company News

Fire Resistant Cable with UL

2021-07-01

                     Fire Resistant Cable with UL


1.    Pressurized stage-CMP level (supply air combustion test / Steiner air duct test Plenum)

This is the most demanding Cable (Plenum Cable) in the UL fire protection standard. The applicable safety standard is UL910. The experiment stipulates that multiple samples should be laid on the horizontal air duct of the device and burned with an 87.9KW gas Bunsen burner (300,000BTU/Hr) 20 minutes. The eligibility criterion is that the flame cannot extend beyond 5 feet from the front end of the gas Bunsen burner. The peak value of the optical density is at most 0.5, and the average density value is at most 0.15. This kind of CMP cable is usually installed in the air return pressurization system used in ventilation ducts or air handling equipment, and is approved for use in Canada and the United States. FEP/PLENUM materials conforming to UL910 standard have better flame retardancy than low-smoke halogen-free materials conforming to IEC60332-1 and IEC60332-3 standards, and the concentration of smoke when burned is lower. CMP-class cables must pass a rigorous combustion test: UL910-"Flame Spread and Smoke Density Value Test"



2. Trunk CMR level (Riser Flame Test)


This is a Riser Cable in the UL standard, and the applicable safety standard is UL1666. The experiment stipulates that multiple samples are laid on the simulated vertical shaft, and the specified 154.5KW gas Bunsen burner (527,500BTU/Hr) is used for 30 minutes. The eligibility criterion is that the flame cannot spread to the upper part of a 12-foot-high room. There is no smoke density specification for trunk-level cables, and they are generally used for floor vertical and horizontal wiring. CMR-class cables must pass the intensive flame test: UL1666-"Test for the height of flame propagation of cables installed vertically through to the middle"


3. Commercial CM grade (Vertial Tray Flame Test)



This is a general purpose cable in the UL standard, and the applicable safety standard is UL1581. The experiment stipulates that a number of samples are laid on a vertical stand of 8 feet high, and burned with a prescribed 20KW belt burner (70,000BTU/Hr) for 20 minutes. The qualification standard is that the flame cannot spread to the upper end of the cable and extinguish itself. UL1581 is similar to IEC60332-3C, except that the number of cables to be laid is different. Commercial-grade cables do not have smoke density specifications, and are generally only used for horizontal wiring on the same floor, not for vertical wiring on the floor.



4. General-purpose CMG level (Vertial Tray Flame Test)

This is a General Purpose Cable in the UL standard, and the applicable safety standard is UL1581. The test conditions of commercial grade and general grade are similar, and they are both approved for use in Canada and the United States. There is no smoke density specification for general-purpose cables, and they are generally only used for horizontal wiring on the same floor, and not for vertical wiring on the floor. The CM/CMG cable jacket is usually made of some kind of PVC, which emits chlorine gas in the combustion chamber. CM/CMG grade cables are usually used in horizontal wiring in the UK, Asia and Australia. CM/CMG cable must pass CSA FT-4 "Vertical Burning Test"



5. Household CMX Level Cable (Vertial Wire Flame Test)


This is a Restricted Cable in the UL standard, and the applicable safety standard is UL1581, VW-1. The experiment stipulates that the sample should be kept vertical and burned with the test burner (30,000 TU/Hr) for 15 seconds, then stopped for 15 seconds, and repeated 5 times. The qualification standard is that the residual flame should not exceed 60 seconds, the sample should not be burned by more than 25%, and the surgical cotton pad on the bottom should not be ignited by falling objects. UL1581-VW-1 is similar to IEC60332-1, except that the burning time is different. This level also has no smoke or toxicity specifications, and is only used in home or small office systems where a single cable is laid. This type of cable should not be used in bundles, but must be sleeved. Smoke density, halogen content and toxicity level. The CMX Cable must pass UL VW1 burning test