When the transformer is out of phase， there is still no sound when the second phase is sent， and there is sound when the third phase is sent; If the third phase is blocked， the sound will not change， which are called test power transformers. They can be divided into inflatable oil transformer， dry test and other test power transformers. They are the basic test equipment for communication AC compression test for many consumers such as power stations， power supply bureaus and scientific research institutions. According to the specifications of the Bureau of quality supervision， It is used to carry out insulation compressive strength test under required current for various electrical products， electrical components and insulating raw materials.
Kenia gewattsStep up process of dry-type transformer?
Brief introduction of zero line of power transformer
Malo ancetraAfter no-load test run is normal for h， it can be transferred to on-load operation， and the load shall be gradually increased from % % and % by grade.
After the test， connect the data signal contact of the automobile relay with the alarm circuit， the pull-in contact with the opening circuit， and adjust the overcurrent protection value.
In relay protection dry-type transformer， the disconnection of the fault point is related to each other. In a word， if there is any problem at a certain point， it will affect the whole power circuit
Oil immersed transformer
The appropriate power saving calculation formula should be derived from the following process: active power loss of large capacity transformer: load of large capacity transformer; PDK - short-circuit fault loss of large capacity transformer， kW. Active power loss of small capacity transformer: when a pump room is in normal operation， and each pump is driven by kW motor， so the usual load is KW， CST = . One kva transformer was originally configured， and the capacity utilization rate introduced by the transformer manufacturer is only %
The tail end of the high-voltage winding head and the middle tap are made of copper inserts and embedded parts， with good strength and stiffness， which is conducive to adjusting the data and has a unique and neat style.
TrustworthyThe vibration reduction of the grounding device sheet solves the problem of modifying the fixed hard connection between the copper sheet of the grounding device and the dry-type transformer. The original oscillation of the dry-type transformer will be transmitted to the metal in the concrete by the baffle and cause low-frequency noise. Therefore，Kenia gewattsPrice of 200 KVA oil type transformer， it must also be changed to produce flexible connection.
The tap changer of power transformer shall also have strong insulation. kV off load tap changer is generally insulated from the ground by the produced insulating paper pipe factory.
Difference between dry-type transformer and oil immersed transformer:
Use fiber materials to seal the bolts to achieve the goal of controlling leakage. The other is to screw out the bolt (nut)， wipe the Fushi blue film remover on the surface， and then tighten it after wiping the raw materials on the surface. After drying， the treatment goal can be achieved.
consumptionThe input and output three-phase power lines shall be connected to phase a， phase B and phase C respectively according to the color of yellow， green and red bus duct of transformer terminal board. The zero line shall be connected to the neutral zero line of transformer voltage，Kenia gewattsPrice of dry-type transformer， and the grounding wire， transformer casing and its transformer point shall be connected to each other. At ordinary times， the ground wire and zero wire are led out by the neutral wire of the transformer. (for example， the transformer box shall be matched with the ground wire mark of the shell and connected with each other). Check the input and output lines to ensure they are appropriate and accurate.
First of all， although dry-type transformer has strong moisture resistance， it is generally open structure or very susceptible to moisture， the dry-type transformer can obtain high stability only when the air humidity is below %. The dry-type transformer shall also be prevented from stopping operation for a long time to prevent serious damp. When the grounding resistance value is less than / V (operating voltage)， it indicates that the transformer is seriously damp， and the trial operation shall be terminated.
The clock expression is used to indicate the phase difference correlation of the working voltage of the secondary side line. The phasor of the working voltage of the primary side line is used as the minute hand， the fixed finger is at o"clock， and the phasor of the phase voltage of the secondary side is used as the second hand.
Kenia gewattsThe no-load impulse closing working voltage shall not exceed % of the working voltage marked on the gear of the transformer， the closing frequency shall be times， the delay time after power receiving shall not be less than min， and the time interval of each closing shall not be less than min.
When sampling from a small and medium-sized power transformer without a discharge pipe (or oil sample suspension plate)， 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.
The long-term overload of power transformer will slowly cause the scalding and insulation aging of solenoid coil， resulting in short circuit between coils， two-color short circuit or short circuit on the ground， resulting in the ignition of power transformer. Therefore， the insulation compressive strength of power transformer shall be tested before installation and operation， and overload is not allowed in the whole process of operation.
