For 40.5kV circuit breaker, floor type-mounted seems to be more convenient, the operating mechanism is located directly at the bottom of the pole column, the depth of the handcart can be reduced, the handcart is convenient to pull the handcart out of the cabinet, without the need to transfer the handcart, after all, the 40.5 circuit breaker is very heavy, generally about 300kg, the handcart to advance, pull out a person can not be operated at all, advancing the cabinet guide rail alignment is not a simple matter, often need to be adjusted over and over again, the centre-mounted type […]

The customer’s requirement is to pass an internal arc fault test with a 40kA 1s rating for a 17.5kV switchgear cabinet that is 650mm wide. Switchgear Cabinet Dimensions: Width: 650mm Depth: 1400mm Height: 2200mm Phase Spacing: 150mm Rated Voltage: 17.5kV Rated Power Frequency Withstand Voltage: 38kV Rated Lightning Impulse Withstand Voltage: 95kV Rated Current: 1250A Rated Short-Time Withstand Current: 31.5kA Rated Peak Withstand Current: 82kA Rated Internal Arc Class: IAC A FLR 40kA/1s The first mapping test revealed some of the following problems: (1) Firstly, the rivet pulling nut will be pulled apart under the huge shock wave impulse; (2) […]

Contactors find application in various scenarios where the switching on and off of loads is necessary during normal operations. These applications include medium voltage public lighting and industrial motors. The combination of a medium-voltage contactor and a fuse controller, such as the F-C controller, is capable of controlling motors up to 12 kV. These medium-voltage controllers can also serve as feeders for other load types, particularly transformers. In cases involving transformers, contactors are often modified to incorporate mechanical holding features, ensuring that the contactor does not open automatically in the event of a system voltage collapse. Mechanically held contactors, which […]

Low and medium voltage electrical components of the electrical parameters, many are similar, such as short-time withstand current Icw, are required to switchgear in the case of short-circuit faults, due to the circuit breaker tripping time required or faults caused by the absence of tripping, or sectional protection needs to be switched to withstand a certain amount of time of the short-circuit current, and therefore there is a parameter requirement of the Icw. Icw includes two parts, one is to withstand the rated short-circuit current rms (rms), such as medium voltage short-time withstand current 31.5, 40, 50kA, etc., low-voltage short-time […]

While there are many formulations of alicyclic epoxy resins and many varieties of ceramics, each with their own specific qualities and parameters, there are some general comparisons . First, in the physical realm, the following relationships are typical: – The weight of an alicyclic epoxy resin is less than 70% of the weight of porcelain, which means that epoxy insulators are much lighter than porcelain insulators. – The coefficient of thermal expansion of epoxy is 1/20th that of porcelain. – The tensile strength of epoxy resin is about 11 times that of glazed porcelain. – The compressive strength of epoxy […]

Complete sets of equipment for rated voltages not exceeding 1000V AC and 1500V DC, fixed or mobile, with or without enclosures One or more low-voltage switchgear and related control, measurement, signalling, protection, regulation and other equipment, by the manufacturer is responsible for the completion of all the internal electrical and mechanical connections, with structural components completely assembled together in an assembly. Role of low voltage switchgear. ~ power distribution conversion, motor control, reactive power compensation and other purposes. ~Protection of persons against electric shock (direct and indirect contact); ~Protection of equipment against external environmental influences. ~Protection of equipment against external […]

split-type and common box type ring network cabinet, with the high level of manufacturing, the power supply department of the ring network cabinet requirements, so the split ring network cabinet used more and more. Split type, ring network cabinet in full accordance with the switchgear form of design and production, that is, each unit is an independent individual, individual with the same cabinet between the external connections, such as bus connecting bushings, grounding rows, secondary routing holes as well as inter-cabinet connection holes and so on. Split benefits, individual cabinets, can be combined according to the needs of the project, […]

Low and medium-voltage switchgear, customised to order requirements and according to specific electrical system diagrams. Engineering requirements vary and it is difficult to standardise and define products. Although the MNS low-voltage cabinets, KYN28 middle cabinet mechanism, appearance is similar, but the specific implementation of the project, large to the current specifications cabinet size, small to the transformer indicator and other control circuits may be different. Switchgear project first need to project how big, how many incoming, incoming transformer capacity, how many outgoing, how many transformer outgoing, transformer out of how much, transformer out of the capacity is how much and […]

Double-layer switchgear is not a new concept; it dates back to the 1950s when the United States introduced metal-clad double-layer withdrawable switchgear. This innovative design featured two double circuit breakers, eliminating the need for a separate instrument room. Instruments were integrated onto the door of the circuit breaker room, while relays, terminals, and other components found their place on both sides and upper and lower sections of the circuit breaker room. In addition to circuit breakers, these double-layer switchgears incorporated various functional units, including voltage transformers, fuses, current transformers, and handcart units. This flexibility allowed for a wide range of […]

Medium-voltage metal-clad withdrawable switchgear cabinets require a contact box. The so-called contact box is actually a common name in the industry for an insulating sleeve used to install static contacts and to provide electrical isolation from grounded parts such as the mounting plate and the busbar phase. Why need contact box? Withdrawal type i.e. circuit breakers and other functional hand trucks need to be connected to the main circuit, hence the need for primary contacts. Why metal armoured? The definition of metal armoured switchgear cabinet, each functional compartment is completely separated by grounded metal plates, and the electrical connection between […]