The fireproof bridge is suitable for power cables below 10KV, as well as indoor and outdoor overhead cable trenches and tunnels for control cables and lighting wiring.
The fireproof bridge is mainly composed of a composite of a fiberglass reinforced material and an inorganic binder combined with a metal skeleton and other fireproof substrates. The outer layer is coated with fireproof coating. The fireproof bridge will not burn after fire, thus blocking the spread of fire. It has excellent fire and fire retardant effect, and has fire resistance, oil resistance,
In this issue, let's talk about the heat dissipation problem of the power supply, including the importance of heat dissipation, the heat dissipation method, the main heating components inside the power supply, and the requirements of the upper temperature limit of each key point.
First of all, understand the current user's awareness of power supply cooling: the majority of DIY users have a high degree of attention on CPUs, graphics cards, motherboards and other accessories that can directly affect the performance of the
The cable tray is divided into a trough type, a tray type, a ladder type, a net format and the like, and is composed of a bracket, a support arm and a mounting attachment. The bridge inside the building can be erected independently, or it can be attached to various building (structure) and pipe brackets. It should be characterized by simple structure, beautiful appearance, flexible configuration and convenient maintenance. All parts need to be galvanized. , installed in the open-air bridge outside the building.
Cable tray busway is widely used and has a wide range of applications. In particular, dense insulated busway (hereinafter referred to as busway) can be AC three-phase three-wire, three-phase four-wire, three-phase five-wire system, frequency 50 ~ 6OHz, voltage to 400V, rated working current is 250 ~ 5000A, mainly as industrial and mining New power supply and distribution equipment in enterprises, enterprises and high-rise buildings. The busway with socket can be easily led out of the power supply by plugging the connector box or the plug-in switch box. The cable tray busway has the advantages of small size, compact structure, large transmission current and convenient maintenance. The installation of the cable tray busway can be directly connected from the transformer to the low-voltage distribution cabinet, or directly from the low-voltage cabinet to the distribution system as the distribution trunk line.
The busway conductor is copper or aluminum, and the service life of the busbar is critical depending on its operating temperature. The higher the operating temperature, the faster the aging rate (including copper, aluminum and insulation materials. Electrical copper and electrical aluminum for conductors, their creep strength, tensile strength and oxidation rate are closely related to temperature) . Because the busbars have different design and heat dissipation, the internal temperature is different. According to the conductor table of the design manual, the ambient temperature is 35 °C, and the dense busbar with better heat dissipation can reduce the current carrying capacity by 5%~15% to meet the temperature rise value of ≤70K. The dense busbar with poor heat dissipation should be reduced by 20%. About %, the air-carrying capacity of the air-type busbar is reduced more.