The core value of fire-resistant busway lies in its continuous power supply capability under fire conditions. According to national standards, a genuine fire-resistant busway must maintain power supply for 1-3 hours at a high temperature of 950°C, ensuring the normal operation of critical facilities such as emergency lighting, fire pumps, and smoke exhaust systems.
The key to identifying quality lies in verifying its fire resistance time rating. Currently, the market offers four grades: A (30 minutes), B (60 minutes), C (90 minutes), and D (120 minutes). However, the actual requirements for many important projects often exceed these standards, often demanding proof of fire resistance for 180 minutes or even longer.
The most professional testing method involves conducting both spray test and fire resistance test simultaneously: first, heat the sample joint for a period of time using a flame (750°C - 800°C or 950°C - 1000°C), then spray water according to specifications, simulating the actual situation after fire suppression water is applied during a fire.
1. Conductor material is the primary point of inspection. High-quality refractory busbars use electrolytic copper of high purity (≥99.9%), fully tin-plated, with conductivity ≥97%. Some unscrupulous merchants may use fraudulent methods like copper-clad aluminum. This can be identified by requiring suppliers to provide material certificates or conducting on-site sampling inspections.
2. Insulating materials are directly related to fire resistance. High-quality products use materials like mica tape and ceramicized silicone rubber, which can withstand high temperatures, to wrap conductors, maintaining their insulating properties even when exposed to high heat. Flame-retardant, halogen-free materials at B grade and above are the basic requirement, with heat resistance temperatures of ≥130°C.
3. Don't overlook the casing craftsmanship. High-quality products use steel or aluminum alloy profiles for casings, offering thickness and durability to withstand high-temperature impacts during fires and mechanical collisions. The surface treatment should include processes such as pickling, phosphatizing, powder coating, and curing.
Fire-resistant busway, in addition to the conductive function of a regular busway, must maintain circuit integrity for a certain period under flame conditions. Our fire-resistant busway products have passed the GA/T537-2005 standard test, maintaining circuit integrity for over 180 minutes under flame conditions.
Fire-resistant busway technical specifications:
Rated Voltage: 400-690V
Rated Insulation Voltage: AC 1000V
Protection Rating: IP65
Short-term耐受电流: 50KA
Rated Frequency: 50-60 Hz
Dielectric Strength: AC 3500V
Our fire-resistant busway employs T2*** conductive copper strips with copper content ≥99.95% and resistivity ≤0.01777Ω.MM2/M. The conductor surface is wrapped with 3 or more layers of mica tape insulation (with heat resistance ≥1100°C), and the conductor and housing are separated by silicone wool (with heat resistance ≥1600°C) for thermal insulation. The housing is made from 2.0mm or thicker *** steel plate, which is then statically coated with fire-resistant powder after being de-rusted, de-oiled, and phosphated and dried, ensuring that the housing does not burn in flame conditions. The housing structure features both inner and outer channels, preventing direct or indirect flame from burning the conductor or damaging the insulation, while ensuring the necessary protection level in spray-down conditions and maintaining circuit integrity.
