Before and after sampling clean the periphery of the sampling port with clean or hairless linen.
The dry-type transformer is composed of two winding resistances， resulting in four wiring groups: & ldquo; y， Y & rdquo;， & ldquo; D， Y & rdquo;， & ldquo; y， D & rdquo; and & ldquo; D， D & rdquo;. In China， only & ldquo; y Y & rdquo; and & ldquo; y， D & rdquo; are selected. Because there are also two types of Y-connection with neutral line and without neutral line. If there is no neutral line， it will not be upgraded. All marks show that with neutral line， it will not be upgraded The letter N after the English letter Y indicates that the neutral line has transformer grounding wire. Yn wiring group， when UAB and UAB overlap， the minute hand points to . & ldquo; & rdquo; in the new wiring group， it is indicated by & ldquo; & rdquo.
Alan jerowacPower saving analysis of transformer
The project cost is different. Compared with the purchase price of capacity transformer， the purchase price of dry-type transformer is much higher than that of oil immersed transformer.
HaodaThe voltage regulating tap changer is not in place or poor
When sampling from a small and medium-sized power transformer without a discharge pipe (or oil sample suspension plate)，Alan jerowacLightning protection of distribution transformer， it can be in a power transformer such as a glass test tube when it is not in operation to extract the oil sample at the bottom， or it can be replaced by changing the oil.
Naturally， if the oil immersed transformer catches fire， please be rational to make the oil immersed transformer safer and more efficient.
Analysis of common faults of oil immersed transformer:
The step-up dry-type transformer refers to the instantaneous operation of voltage. At this stage， there are few manufacturers of dry-type transformer that can reasonably guarantee the instantaneous step-up in China. The step-up dry-type transformer has strong step-up capacity and good practical effect. The difference depends on that the transformer power switch without excitation regulator does not have the ability to change gear with load. Because this kind of tap power switch can cut off the whole process in a short time during the whole process of gear change cutting off the load current will cause arc burning between circuit breakers， tap power on and off or short circuit fault， so the dry-type transformer shall be powered off during regulation. Therefore， it is generally used as a dry-type transformer that is not very strict in voltage regulation and does not need to be adjusted frequently.
The capacity and working voltage are different. The dry-type transformer is generally suitable for distribution equipment. The capacity is generally below kVA and the working voltage is below KV， which also ensures the rated voltage of kV; Oil immersed transformers are generally suitable for distribution equipment.
Total quality managementBefore no-load impact closing， the pose period of overcurrent protection shall be set to zero， the closing frequency shall be times， the delay time after power receiving shall not be less than min，Alan jerowacImpedance standard for dry type transformer， and the time interval of each closing shall not be less than min.
The heat discharge pipe of heat pipe radiator is generally made of slotted seamless steel pipe after flattening by stamping die. When the heat discharge pipe is bent and welded by electric welding， oil leakage is often caused. This is due to the supporting force on the surface of the pipe and the working pressure on the inner cavity when stamping the heat discharge pipe.
After tightening the loose bolts， seal the flange， so as to achieve the goal of complete treatment. Tighten the loose bolts strictly according to the actual operation and processing technology.
Service firstDry type transformer
The dry-type transformer used for power plant voltage transformation is different from the oil transformer. It is strictly prohibited to lead the way at the bottom voltage side to prevent the insulation layer of the dry-type transformer from penetrating due to overvoltage caused by overvoltage at the power grid side or lightning stroke on the line.
() the installation position of secondary commercial insurance of transformer on column and ground shall meet the following requirements: if there is an disconnector on the secondary side， it shall be installed between the disconnector and low-voltage composite insulator，Alan jerowac315 KVA oil immersed transformer， or the circuit breaker shall be selected as the disconnector; If there is no disconnector on the secondary side， it shall be installed on both sides of the low-voltage composite insulator， and the insulated cable jumper shall be connected to the insulated cable on both sides of the circuit breaker.
Alan jerowacMethod and process of taking oil sample of power transformer
The power transformer is composed of two or more electromagnetic coils wound around the same transformer core. The winding resistance is connected according to the alternating electromagnetic field and works according to the basic principle of magnetic effect of current. The installation position of power transformer shall be considered to be conducive to operation， maintenance and transportation， and a reliable area shall be selected at the same time. The rated capacity of the transformer must be effectively used when applying the transformer.
The insulating layer in the middle of the silicon steel plate is aging， the anchor bolt cover with the iron core is damaged， the iron core causes large vortex， resulting in heat， temperature rise， and the aging of the insulating layer is accelerated. The core insulation compressive strength of power transformer must be measured on time and accurately. If it is found that the insulation compressive strength is less than the index value， please remove and replace the anchor bolt cover or carry out insulation for the copper core cable.
