Before the detailed structural description of the fire alarm line, it is best to understand the product certification of the fire alarm line, if not, it is easy to get confused. We currently need to understand what the main certification of fire alarm line products: (1)the United States UL1424 certification; (2)the British LPCB certification.
(1) the United States UL1424 certification
What is UL:
UL is the English Underwriters Laboratories (Underwriter Laboratories Inc.) abbreviation, is the largest U.S. product safety testing and certification organizations, and more of its certification is in the civilian products, according to the UL series of standards for certification, UL standard self-contained system, and other foreign standards do not communicate (and the IEC International Electrotechnical Commission's standards are not the same).
UL Safety Testing Institute is the most authoritative in the United States, but also in the world engaged in safety testing and identification of the larger private institutions, it is mainly engaged in product safety certification and management of safety certification business, the ultimate goal is to get for the market with a considerable level of safety of goods, to ensure the safety of personal health and property to contribute to.
Introduction to UL1424 - Power Limted Fire Alarm Cable:
Scope: These requirements cover 60 to 250°C single and multi-core cables used as fixed wiring in buildings (some are also labeled for direct burial), primarily for power-limited fire alarm circuits. The cable smoke and fire test requirements covered by these requirements are as follows:
a) Type FPLP (inflatable cable)
FPLP Cable Type - Cables installed in duct air chambers or other spaces used for the transfer of ambient air without sealing the cable, tested for smoke and flame characteristics in ducts in such spaces in accordance with the National Fire Protection Association Flame Propagation and Smoke Test Standard for Cables for Air Handling Spaces.
Compliant cables have a maximum flame propagation distance of not more than 5 feet or 152 cm, produce smoke values with an optical density of 0.50 or less (transmittance of 32%), and have smoke values of 0.50 or less.
(32% light transmission), and the average optical density of the smoke is 0.15 or less.
b) Type FPLR (Lifting Cable)
FPLR Cable Type - Used for cables in shafts in shafts or cables penetrating more than one floor of an installation. The flame propagation characteristics of this cable are tested in accordance with UL1666 Standard Test for Light Propagation Height for Cables Installed Vertically in Shafts. Compliant cables have a flame propagation height of not more than 12 feet or 366 cm and a temperature of 454.4°C (850F) or less.
c) Type FPL (Vertical Pallet Flame Test)
FPL Cable Type - Meets the 70,000 Btu/h (20.5kw) vertical tray flame test. UL1685 FPL cables connected to surfaces that are marked or designated shall not appear to coke to the upper end of any specimen (8 ft. or 244 cm maximum).
Other testing requirements for electrical performance include: cold bending test of insulation, conductor resistance test, insulation resistance test, long term insulation resistance in water test, and so on.
test, insulation resistance test, long-term insulation resistance test in water, etc.
(2) LPCB certification in the United Kingdom
What is LPCB: LPCB is the acronym of Loss Prevention Certification Board, which is the standard in the field of security and fire protection in the UK.
LPCB certification is equivalent to the product has met the British standard certification.
The scope of products certified by LPCB mainly includes the following categories:
--Building products
--Fire monitoring and alarm systems
--Wires and cables
-Fire extinguishing products and systems
-Safety and protection products
In the wire and cable, LPCB certification than UL1424 certification requirements are higher, such as LPCB fire-resistant cable requirements to achieve BS6387CWZ (fire-resistant cable testing requirements through the horizontal combustion test, water spray test and mechanical shock vibration combustion test) need to carry out the following three tests, this is a little bit of difficulty, but also is the world's highest standard of fire-resistant cables:: a), BS6387 Category C: 950 ℃ flame through the fire, but the fire-resistant cable is also the highest standard.
a)BS6387 Class C fire-resistant cable: withstand 950 ℃ flame burning 180 minutes; -- simple fire test
b) BS6387 W class fire-resistant cable: withstand 650 ℃ flame burning 15 minutes and water spraying 15 minutes; - fire-resistant water spraying test
c)BS6387 Z class fire-resistant cable: withstand 950 ℃ flame burning and mechanical shock for 15 minutes. --Fire-resistant vibration test
Secondly, BS EN50200-2015 Methods of fire resistance test for unprotected small cables for emergency circuits intended for use as emergency circuits for alarm, lighting and communication purposes.EN 50200 applies to emergency circuit cables with rated voltages up to 600/1 000 V, including cables with rated voltages of less than 80 V, as well as to emergency circuit fiber optic cables. This standardized test method is limited to cables with an overall diameter of up to 20 mm.
The EN50200 test method is similar to BS6387, but with classification requirements. The test method consists of installing a cable sample of 1200 mm in length in the laboratory and applying a voltage at the nominal value of the core during the test to produce a closed circuit. During the test, the cable is subjected to a conventional temperature of 842°C
Mechanical strokes are subjected to flame action for a specific time period. The measured time of normal operation of the cable corresponds to the so-called fire resistance class PH as follows:
Test durations are expressed in minutes and recorded in the following classifications:
PH 15: Flame exposure for 15 minutes
PH 30: Flame exposure for 30 minutes
PH 60: Flame exposure for 60 minutes
PH 90: Flame exposure for 90 minutes
PH 120: Flame exposure for 120 minutes