How to solve the problem of single phase grounding fault in motor
For small current grounding system, how to find a single phase to ground fault, we can use the manual to find fault.
If substation without installation of grounding line selection device, line nor install grounding fault indicator or short circuit grounding combo fault indicator, also not very good grounding fault detector, it had no choice but to use manual search is a stupid way. Search steps are as follows:
(1) there are two ways to find fault point: first, the line level, or the regular fault lines, using 2.5kV shake table to measure the insulation resistance of the fault section, so as to narrow the search range (of course, the line must be connected to the power line and other security measures); two is the line as possible, and then step by step, with the dispatch of zero sequence voltage.
(2) by means of an artificial (or scheduling, following the same), a gate may be drawn to know which of the substation is connected to the ground, which is known to be connected to the ground.
Manual search method operation is very troublesome, if the line is long, many branches, switches, and less, it is not good to operate, plus the weather and the weather is not good, it is not good to deal with the. It is suggested that the use of some equipment to invest in scientific and technological means to coordinate with manual search, can get twice the result with half the effort, not only provides the power supply reliability and social benefits, but also created economic benefits.
Industry focus
"In the first half of 2015, China's industrial and economic operation of the positive factors increased, stable and slow, steady in a good situation." In the press conference, the Ministry of industry and information technology spokesman Zhang Fengru is a summary of the general engineer. According to the National Bureau of statistics, in the first half, above scale industrial added value grew by 6.3%, the growth rate down 2.5 percentage points.
However, several indications also show that China's industrial operation has improved. Data show that in June, Manufacturing Purchasing Managers Index has four consecutive months in the ups and downs of the line above, above scale industrial added value increased by 6.8% growth for three months rebound. 4, 5 and two months of above scale industrial enterprises realized profits increase from negative to positive growth of 2.6% and 0.6%, respectively.
Ministry of industry and information technology operation monitoring and Coordination Bureau deputy director Huang Libin introduction, at present, China's industrial economic operation in the slow stabilization, steady progress, into memory concerns. From stimulating industrial growth "3 drive carriage" point of view, consumption, investment in April and may, appeared the momentum of recovery, signs of stabilization have noticeably increased, stabilization forces constantly gathering.
"In recent years, some of the transformation of early, adjust the pressure of the provinces to be a little less pressure." Huang Libin introduced, such as the first half of Jiangsu, Guangdong, Shandong, the scale of industrial added value is 8.3%, 7.4% and 7.4%, while Henan, Anhui, Jiangxi, Hubei, Chongqing, the increase of more than 8%.
It is noteworthy that, according to the Ministry of industry statistics, in the first half of 41 major categories, the first half of this year, there are 23 industries increased faster than the average growth rate, the average growth rate reached 8.4%.
Zhang Feng introduced policies to encourage the industry to support the situation is good, the new industry development is relatively fast, to accelerate the adjustment and upgrade to make positive progress, bio medicine, electronic information, high-end equipment, software services and other emerging industries rapid development. In the first half, high tech manufacturing industry increased by 10.5%, significantly faster than the overall level of industry.
With the development of the Internet +, many new formats continue to emerge, the scale of China's Internet industry continues to expand, the ability to continue to enhance innovation. As of the end of 6, the total market value of listed Internet companies increased by 96.5%, 12 Internet companies into the world's top thirty, a record high, the Internet economy as a representative of the new growth point rapid formation.
