External Factors and Solutions to the Electrical Control System of Concrete Electric Pole Equipment
Electric parts of concrete pole are different in terms of material construction, appalication and so on. However, we found that the same electrical equipment in different use of the environment, the degree of loss is also very different, life difference is very large. Different natural environment on the impact of different equipment, such as temperature, humidity, etc. may become the main factors affecting the electrical equipment. Therefore, according to these factors to develop different countermeasures, to take targeted measures, will be conducive to the smooth development of electrical equipment management.
1. The impact of external environmental factors on electrical equipment
Almost all electrical equipment in the technical indicators have on the ambient temperature, humidity, altitude, vibration and other places of use of environmental restrictions. This shows that external environmental factors have a very significant impact on electrical equipment. It will directly or indirectly affect the equipment failure rate, life, and even whether the normal work. Therefore, it is of great significance to explore the impact of external environmental factors on electrical equipment for electrical equipment management.
1.1 temperature electrical equipment running process, the temperature is too high or too low, long-term beyond the required allowable range, are likely to cause equipment failure. Temperature is too high, copper and aluminum conductive metal materials such as long-term working temperature limit, the metal material may soften, the mechanical strength will be significantly decreased; electrical contact conductor surface oxidation, contact resistance increased significantly, poor conductor contact, electrical contact stability is poor; For insulation materials that are classified according to the ability to withstand high temperatures, the temperature overrun can lead to the aging of the insulating material, the performance degradation and even the breakdown. The ambient temperature is too high or the air flow is poor and the heat dissipation is poor, which will lead to the stability and reliability of the equipment. Sexual and accuracy of the decline, easy to overheating trip, or even damage. Low temperature environment on the electrical appliances in the oil, spring, LCD, electronic chips and other effects can not be ignored.
1.2 Humidity and humidity will reduce the electrical insulation of the electrical equipment. On the one hand the humidity is too high, the air insulation performance is reduced, easily lead to short circuit failure. On the other hand, the moisture in the air adheres to the surface of the insulating material, which reduces the insulation resistance of the electrical equipment, especially the equipment with longer life. After the internal dust absorbs moisture, the insulation resistance is lower, which is easy to cause the breakdown breakdown. Moreover, the humidity is conducive to the growth of mold, easy to damage the insulation properties of equipment. As we all know, humid air easily lead to electrical equipment inside and shell metal parts corrosion, easy to reduce its performance and service life, lead to electrical failure.
1.3 dust dust, not only will pollute the environment, damage the health of people, but also the safe operation of electrical equipment hazards. Such as dust in the top of the circuit breaker condensation settlement is likely to cause interphase insulation strength greatly reduced, induced phase short circuit accident. Dust in the relay, contactors and other contacts between the accumulation of easy contact caused by poor failure. If the dust is blocked, the equipment will be poorly cooled, the temperature rise is too high, the equipment may not work properly.
1.4 The impact of altitude elevation on electrical equipment is mainly reflected in the insulation strength, breaking capacity and temperature rise in three areas. The higher the altitude, the lower the air pressure, the corresponding reduction in the density and humidity of the air, and the reduction in the outer dielectric strength. The electrical gap breakdown voltage drops, the air dielectric switch electrical arc performance is reduced, the equipment breaking reliability is reduced. The higher the altitude, the cooling effect of the air medium is reduced, the cooling capacity is reduced, and the ultraviolet radiation is enhanced, the insulating material is easy to be aged, and the electrical equipment is prone to failure.
1.5 vibration vibration will cause electrical equipment parts fatigue damage, wear and loose, so that equipment can not work properly. For the contact components, the vibration can easily lead to poor contact; for the chassis and the base, the vibration is prone to frequent fracture or deformation. Data show that vibration will also increase the probability of dust into the electrical inside.
1.6 people and animals or animals intentionally or unintentionally touched the electrical equipment caused by electric shock or equipment malfunction, prone to personal injury or electrical failure. The main reason for the occurrence of the device is to protect the device is missing or set unreasonable.
1.7 Other other factors are some unpredictable external factors, such as storms, lightning, heavy snow and other adverse weather caused by force majeure. Such as the storm blowing pole pole wire, lightning led to tripping and so on. In a certain period of time there is a great chance of such abnormal weather, the equipment management personnel should be prepared in advance, targeted to carry out electrical equipment inspection and maintenance.
2. Impact on the development of countermeasures
2.1 heatstroke, anti-freeze measures High temperature weather, taking into account the impact of temperature rise, electrical equipment to take "heatstroke" measures, including the strengthening of ventilation management to ensure that the equipment area and the equipment itself, the heat; due to high temperature lead to easy to flow out of bearing lubricants; Equipment inspection, timely reflect the equipment of the abnormal temperature rise, sound, vibration, etc .; work in high temperature environment, electrical equipment, cooling fan can be forced to cool. Winter low temperature weather, should pay attention to prevent oil pressure control of electrical equipment due to hydraulic oil viscosity can not be normal start and run, need to advance into the electric heater, do "antifreeze" measures.
2.2 dehumidification measures Environmental relative humidity is too high for the normal operation of electrical equipment will cause a greater threat. Therefore, reasonable measures to reduce the impact of environmental humidity on the operation of electrical equipment, targeted indoor and outdoor environment for moisture dehumidification is very necessary. Effective moisture dehumidification measures include: to take ventilation, local isolation and other dehumidification measures, if necessary, to the electric control cabinet covered with waterproof cover; conditional installation of air conditioning or industrial dehumidifier, quickly solve the wet problem; to prevent condensation, The appropriate location in the electrical cabinet installed heating or drainage dehumidifier; plug the indoor and external cable channel mouth, in the anti-small animals at the same time can prevent moisture and water into; to prevent roof roof water seepage; Inspection, timely closed doors and windows and doors; long-term unblocked equipment, there may be damp must first bake, after the shock resistance insulation resistance before delivery and so on.
2.3 Ventilation and dust prevention measures Use of dust in the equipment on the equipment can easily affect the settlement of equipment cooling, resulting in contact with electrical contact or increase the possibility of short-phase short circuit. For work in dusty environment of the equipment, to choose a high degree of protection of the product or take timely ventilation and dust control measures, if necessary, in the key electrical parts can be covered with dust cover. Electrical maintenance personnel should regularly on the cable connector, contactors and circuit breakers and other major electrical components and large motors, substations, transformers and so on dust, regularly check the switch device contacts and wiring, improve the electrical equipment, dust resistance. Conditional electrical cabinet or place, in the ventilation measures, air duct entrance should be set up filter device and to ensure adequate air flow for heat.
2.4 Reasonable choice of product models Electrical equipment selection, the first should be based on the location of equipment, the use of the environment and working conditions, the initial selection of product types and types, such as indoor and outdoor, altitude, ambient temperature and dust and so on. The next is based on the load conditions, operating current, operating voltage and other basic operating parameters to select the exact product model. When calculating the rated current and voltage of the equipment, the influence of the operating ambient temperature and altitude on the rated current and voltage should be taken into account and adjusted accordingly. For example, the height of the non-high-type electrical equipment use environment does not exceed 1000m, when the use of regional elevation exceeds the manufacturer's specifications, due to atmospheric pressure, air density and humidity corresponding to reduce the air gap and external insulation discharge characteristics, Equipment to allow the maximum allowable working voltage correction, another high-profile products or external insulation to improve a level of products. Also in the actual operation, the ambient temperature exceeds the specified reference temperature, because the temperature rise is too high than the equipment acceptable range, also need to modify its rated current. According to the equipment environment conditions to select the appropriate model is to protect the normal work of the premise of equipment.
2.5 to take appropriate protective measures Electrical equipment itself to do the protection of grounding, in order to avoid damage to electrical equipment in the metal shell and the cable on the cable to produce dangerous voltage, resulting in electric shock accidents. Protection grounding device and leakage action protection device with each other to achieve the detection of leakage and equipment protection action. Protection of grounding devices should be intact, so that regular testing. The hazardous parts of electrical equipment should be protected and set up warning signs to prevent people and animals from touching.
2.6 to strengthen the daily inspection, regular inspection and special inspection to strengthen the daily inspection of electrical equipment, regular inspection and special inspection is necessary. Environmental conditions and electrical equipment their own situation with time dynamic changes. Electrical personnel on duty every day to inspect all electrical equipment and found that electrical hazards such as fever, poor contact and other timely treatment to prevent greater electrical accidents. For some large, high-pressure, usually inconvenient to stop the equipment must be planned to regularly check the use of some parking clearance, targeted to conduct a comprehensive inspection. According to the weather conditions, the type of equipment and other organizations such as thunderstorm season special inspection, lifting equipment, special inspection can supplement our specific period of electrical equipment preventive inspection work. The electrical equipment of the daily inspection, regular inspection and special inspection of the three together, electrical equipment management can be done foolproof.
3. Case study
There are four sets 55kw centrifugal spinning concrete pole machine in one prestressed concrete pole factory controlled by frequency variable control cabinet . The environment requirements for control cabinet is : ambient humidity is below 90%. the vapour and water drop should not exist indoor. But in some areas with rainy season , the real situation is : The centrifugal spinning machine always ran in some rainy season and the control cabinet is easy to form water drop especially when long time stop and then start, the frequency changer often breaks. So, the service worker installed one heating dehumidification device and cleared the water which effectively decrease the ambient temperature of frequency changer and decrease the faulty of electric parts.
The impact of external environmental factors on the electrical equipment is an unavoidable problem. Temperature, humidity, dust, vibration, etc. will directly or indirectly to the normal work of electrical equipment poses a threat. Old saying "go out to see the sky", life we often first "look at the weather", predictably solve the trip may be problems. In the electrical equipment management work, we should also face the external environmental factors on the possible adverse effects of equipment, the rational development of targeted countermeasures to effectively minimize the harm caused by the protection of equipment efficient and stable operation.