About Busbar Carrying Capacity
The busbar load capacity is a complex issue, which is a systematic project that needs to be considered within the switchgear system, designed to include cabinet dimensions, cabinet ventilation, and other factors. There are several formulas for calculating current-carrying capacity, all of which are based on the balance between heat generation and heat dissipation. The […]
Why are transformers rated in kVA and not kW?
Transformers are always rated in kVA and not kW As the name suggests, a transformer only transfers power from one circuit to another without changing the values of power and frequency. In other words, it can only raise or lower the values of current and voltage while keeping power and frequency constant. General data is […]
Difference between KYN28A and RMU
Regarding KYN28A center-mounted cabinet and ring network cabinet, these are two concepts. Both of them are switchgear, and switchgear can be categorized according to application, insulation method, structure type and so on. KYN28A center-mounted cabinet is based on the product structure, center-mounted cabinet is an air-insulated metal-enclosed withdrawable circuit breaker switchgear, is relative to the […]
Medium Voltage Switchgear Foreign Project Requirements
1. Introduction With the domestic products going out and the construction of the Belt and Road, more and more Chinese switchgear are also actively participating in the competition of the international market, however, due to the lack of understanding and experience of foreign demand, only some large enterprises can really go out and expand their […]
Switchgear Arc Resistant Faults
Internal arc fault test IAC AFLR 31.5kA/1s, 40kA/1s, and even 50kA/1s, although the risk of arc test is high, there are very many uncertainties, but not through any “special treatment”, through the test is not impossible to pass, the key is that the design of the product must be in full accordance with the internal […]
Medium Voltage Tubular Busbar Switchgear
These two days EP exhibition, Schneider, ABB coincidentally show the medium voltage Tubular Busbar Switchgear. 12kV and 40.5kV air insulated switchgear. Abstract: With the development of carbon peak, carbon neutral, the green, energy-saving medium-voltage switchgear has become the trend of development, in which the use of materials can be saved, reduce non-ferrous metals, etc., the […]
Scheme design of floor type and centre type circuit breaker
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 […]
Design of Internal Arc-Resistant Switchgear
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 […]
Contactor Applications
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 […]
Short-time withstand
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 […]