The switchgear consists of a fixed cabinet and withdrawable components (i.e., handcart). The cabinet's enclosure and partition plates of each functional unit are assembled using aluminum-zinc-coated steel plates. The enclosure protection level of the switchgear is IP4X, and when the circuit breaker compartment door is open, the protection level is IP2X. This cabinet features overhead and cable incoming lines, as well as left and right interconnections, providing versatility in configuring distribution devices to fulfill design requirements. Since installation, commissioning, and maintenance can be conducted from the front, the switchgear equipment can be wall-mounted or arranged back-to-back to save space and reduce overall investment.
Cabinet
The switchgear cabinet consists of four parts: front cabinet, rear cabinet, instrument chamber, and leakage device. These four parts are independently assembled and spliced together. The enclosure and partition plates of each part are made of aluminum-zinc-coated steel plates processed and folded by CNC machine tools and bolted together. Therefore, the assembled switchgear maintains dimensional uniformity, possesses strong corrosion resistance and oxidation resistance, and exhibits high mechanical strength. The switchgear is partitioned into a handcart chamber, busbar chamber, cable chamber, and relay instrument chamber, each with independent grounding and a protection level of IP2X between compartments. Except for the relay instrument chamber, each compartment has a pressure relief passage. The centralized design significantly increases the position of the cable chamber, enabling multiple cable connections. The doors of the switchgear are electrostatically sprayed for impact resistance, corrosion resistance, and aesthetic appearance (color can be customized by users).
A. Handcart Chamber
The handcart chamber is equipped with specific guide rails for the circuit breaker handcart to slide and operate internally. An active door mechanism is installed at the front end of the static contact, ensuring the safety of operators and maintenance personnel.
B. Busbar Chamber
The busbar chamber is used for the installation of the main busbars. Additionally, three holes on the left wall are used to install busbar insulation sleeves to isolate busbars between devices, preventing accidents from escalating.
C. Cable Chamber
The cable chamber can accommodate current transformers, grounding switches, surge arresters, and cables. A slotted non-metallic or non-magnetic metal sealing plate can be installed at the bottom to facilitate on-site construction.
D. Instrument Chamber
The instrument chamber installs various relays, instruments, signal indicators, operating switches, etc. Additionally, a small busbar chamber can be added to the top of the instrument chamber according to user requirements, capable of laying fifteen control small busbars.
E. Pressure Relief Device
Pressure relief devices are installed above the handcart chamber, busbar chamber, and cable chamber. When an internal fault arc occurs in the circuit breaker or busbar/cable chamber, the internal pressure of the switchgear increases with the appearance of the arc. Once the pressure reaches a certain level, the pressure-release metal plate at the top device will automatically open, releasing pressure and venting gas to ensure the safety of operators and switchgear.
Circuit Breaker Handcart
The VD4 vacuum circuit breaker handcart is a product of ABB company, representing the most advanced product internationally. The VS1 vacuum circuit breaker handcart, designed and manufactured by Sanyuan company, is the most advanced product domestically. Both types of circuit breaker handcarts adopt a centralized withdrawable design, facilitating operation, observation, handcart withdrawal, operation, and maintenance. The special design of the circuit breaker handcart ensures the interchangeability of handcarts of the same specification. The movement of the circuit breaker inside the equipment adopts a screw-driven mechanism, making the circuit breaker's entry and exit extremely easy and reliable.
Interlocking Device to Prevent Misoperation
The switchgear equipment is equipped with a safe and reliable interlocking device, fully meeting the requirements of "five prevention".