Outdoor ring main unit
- Data Sheet
With the continuous development, the urban power grid has greatly improved, but still most cities have formed or are forming a large number of electricity load-up areas. The power supply by 10kV from the substation (or branch line) to the user directly is difficult to meet the requirements of urban development, which resulted in a refresh power supply - through the switching substation to supply the power to the users. However, with the urban density increasing, the original construction of the switching substation is limited by the land and the urban planning office, therefore a more advanced and practical power distribution equipment - small-scale outdoor intelligent switching substation (outdoor ring cabinets) is invented, which has not special requirement for site construction and space saving, and has very flexible configuration. The power supply is more reliable, and with advantages of cost save , short period installation and adjustment.
With the development of modern industry, the requirements for automation and intelligence computerization of the electrical equipment are becoming higher and higher. For the management improvement, the utilization of the new technology is a direction of developing, which includes the modern electronic, sensor, communications or computer and internet which can provide the integration of monitoring, protection, control or measurement under the normal or accident condition.
The intelligent small substation (outdoor ring switchgear) is designed on the basis of European substation, which fix all parts of the 10kV switchgear, circuit breakers, load switches, current CT, voltage transformer PT, substation FTU, RTU and communication control terminal (CCU, 10kV metering, automatic copy table, UPS power supply and the indicators) into a movable, sealed and anti-moisture cabinet which made by stainless steel tank. This type product makes the integration of the primary and secondary system and the modularization of the assembly, and the construction period is shortened, and the reliability of the urban power grid operation is greatly increased.
Conditions of Use
Installation Placement: Outdoor
Ambient Temperature: -35 ℃ ~ +55 ℃ Average Max. Daily +40℃, Average Maximum Yearly +35℃
Wind Speed: ≤ 35 m/s
Relative Air Humidity: ≤90%(+25℃)
Gradient of the Ground ≤5°
Seismic Intensity ≤ VIII
No risk of fire hazard, explosion, severe contamination, chemical corrosion and violent vibration.
1 Minute Working Frequency Withstand Voltage
Withstand Voltage of Thunder Impact
Working Frequency Withstand Voltage of Auxiliary Control Circuit
Rated Breaking Current of the Closed-Ring
No-load Transformer Breaking Current
Cable Charging Breaking Current
Short-term Withstand Current (load switch and the main earth switch) 1sec
Closing Current (load switch and the main earthing switch)
Short-term Withstand Current (the grounded switch at the lower end of the fuse) 1sec
Closing Current (the grounded switch at the lower end of the fuse)
Internal Fault Arcing (IEC298) 1sec