A disconnecting switch is an indispensable basic device in a high-voltage power distribution system. Its design purpose is to provide a "visible, physical disconnection point" to ensure complete isolation of the circuit from the power supply during maintenance or repair.
Detailed Explanation of Core Functions
Isolating Power Supply (Safety Isolation)
This is the most essential function of a disconnecting switch. The visible disconnection point provides operators with intuitive safety confirmation, preventing electric shock accidents caused by accidental energization.
Switching Operation (Changing Operating Mode)
In complex power grid structures, it is often necessary to adjust the power supply mode, such as switching the load from one busbar to another, or putting a backup power supply into operation. Disconnect switches, used in conjunction with circuit breakers, enable flexible switching operations, but the "break before close" logical sequence must be strictly followed.
Small Current Switching (Limited Capacity)
While disconnect switches cannot switch large load currents, they can operate on very small currents under specific conditions, such as:
· Unloaded circuits of voltage transformers and surge arresters.
· Unloaded transformers with excitation current not exceeding 2A.
· Unloaded lines with capacitive current not exceeding 5A.
(Note: Specific allowable values should be referred to the equipment nameplate and regulations; requirements vary depending on the voltage level.)
Operating Procedures (Detailed Process)
The operation of disconnect switches must strictly adhere to the "five preventions" requirements, especially preventing the disconnect switch from being opened or closed under load.
1. Power Deactivation Sequence (Before Maintenance)
· Step 1: Disconnect the circuit breaker (cut off the load current).
· Step 2: Open the power-side disconnect switch.
Step 3: Test for voltage and connect the grounding wire (if necessary).
2. Power-on Operation Sequence
• Step 1: Remove the grounding wire (if applicable).
• Step 2: Close the power-side disconnect switch.
• Step 3: Close the load-side disconnect switch.
• Step 4: Close the circuit breaker.
in short
In short, disconnecting switches are the "safety guardians" of the power system. Correct use requires technical knowledge, procedural awareness, and a rigorous attitude.
GW4-126 Outdoor High Voltage Isolating Switch
GW4-126 Outdoor High Voltage Isolating Switch is double-column horizontal rotation. It includes 3 single poles, each pole is a double-column structure, mainly composed of a base and a support insulator. Each pole consists of 2 insulators, which are respectively installed on the bearing seats at both ends and connected by cross-links. It can rotate horizontally within a range of 90°. The conductive part is divided into two halves, which are respectively fixed on the insulator pillars, and the contact is in the middle of the two porcelain pillars. When the mechanism is in motion, one of the pillar insulators rotates 90°, and the other insulating pillar also rotates 90° at the same time due to the connecting rod transmission, and the switch is opened and closed on the same side. In order to ensure the correct operation sequence between the disconnector and the grounding switch, reliable mechanical and electrical interlocking devices are installed on the product and mechanism.
Shaanxi West Power Tongzhong Electrical Co., Ltd.
Our address
Nanpo Village, Chencang Avenue Jintai District Baoji City, Shaanxi Province, China.
86-18091765882
xdtz04@westpowerelectric.com
