RW3-10 Drop Fuse

I. Overview

Dropping fuse and pulling load drop fuse are outdoor high voltage protective appliances. It is installed on the high voltage side of distribution transformer or branch line of distribution line, and is used as short circuit, overload protection and load sharing current of transformer and line. The drop fuse consists of an insulating bracket and a fuse tube. The static contacts are installed at both ends of the insulating bracket and the movable contacts are installed at both ends of the fuse tube. The fuse tube consists of an inner arc extinguishing tube and an outer phenolic paper tube or an epoxy glass cloth tube. The pull-load drop fuse enhances the elastic auxiliary contacts and arc extinguishing cover for dividing and closing the load current.

When the drop fuse is in normal operation, the fuse pipe is tightened by the fuse to form a closed position. When the system fails, the fuse rapidly fuses and forms an arc when the fault current occurs. The arc extinguishing tube is heated by the arc and decomposes a large number of gases. A high pressure is formed in the embassy, and longitudinal blows are formed along the pipeline. The arc is rapidly elongated and extinguished. After the fuse is fused, the lower moving contact loses tension and turns down twice, locking the machine, releasing the fuse pipe, and the fuse pipe falls down, forming an obvious breaking position. When the load needs to be pulled, the contact is pulled by insulating rod. At this time, the active and static contacts are still in contact. The contact is pulled by insulating rod, and the auxiliary contacts are separated. Arc is generated between the auxiliary contacts. The arc is elongated in the narrow gap of the extinguishing cover. At the same time, the gas is produced by the extinguishing cover. When the current passes zero, the arc is extinguished.

II. Usage

Outdoor high-voltage fuses are suitable for power systems with voltage frequencies below 35 kV and 50 Hz. They are used for overload and short-circuit protection of transmission lines and power transformers. The rated load current can only be divided and the mechanical life can be more than 2000 times.

III. Conditions of Use

1. Applicable to the upper limit of ambient temperature of 40 C and the lower limit of - 30 C.

2. No more than 1000m above sea level and no more than 35m/s wind speed

3. Fuses are not suitable for the following places

3.1 A place where fuel or explosion is dangerous.

3.2 Places with violent vibration or shock.

3.3 There are heteroelectrochemical gases and serious air pollution, smoke areas.

IV. Brief introduction of structure

The fuse is composed of base and arc extinguishing device. The lower end of the arc extinguishing tube is equipped with a spring bracket which can rotate. The fuse is always in a tense state to ensure the self-locking of the arc extinguishing tube at the closing position. In the overload or short circuit between the circuit and transformer, the fuse is fused and the fuse is quickly withdrawn from the arc extinguishing tube. The step-by-step exhaust mode solves the contradiction between breaking the large and small current on the same fuse.

V. Model Description
Main technical parameters
Installation dimensions