Resonance problem of fan, shell and other parts.
█ Reason: the resonance of fan, shell and other parts will produce noise, which is generally mistaken for transformer noise.
█ Judgment methods
1) shell: press the shell aluminum plate (or steel plate) by hand to see whether the noise changes. If the change occurs, the shell is in resonance.
2) fan: push the shell of each fan with a dry long stick to see whether the noise changes. If there is any change, it means that the fan is in resonance.
3) Other parts: with a dry long stick against each part of the transformer (such as wheels, fan support, etc.) to see whether the noise changes, such as changes in the resonance of the parts.
█ Solutions:
1) look at the shell aluminum plate (or steel plate) is loose, it is possible to step on the deformation of the installation, need to tighten the screws of the shell, the aluminum plate of the shell is fixed, the deformation of the part of the correction.
2) To see whether the fan is loose, it is necessary to tighten the fastening bolt of the fan, and pad a small piece of rubber between the fan and the fan bracket to solve the fan vibration problem.
3) If the transformer parts are loose, it needs to be fixed.
Installation problem
█ Reason: Bad installation will aggravate the vibration of the transformer and magnify the noise of the transformer.
█ Judgment method:
1) Transformer foundation is not firm or uneven (a corner is suspended), or the bottom plate is too thin.
2) Use channel steel to frame the transformer, which will increase the noise.
█Solution:
1) By the installation unit to the original installation method.
2) Add shockproof rubber pad under transformer trolley to solve part of the noise.
Impact of the installation environment
█ Reason: the operating environment affects the noise of the transformer, and the adverse environment increases the noise of the transformer by 3dB ~ 7dB.
█ Judgment method:
1) Transformer room is very large and empty, there is no other equipment, there is echo.
2) The transformer is too close to the wall, less than 1 meter. Transformer on the corner, wall reflection noise and transformer noise overlay, so that the noise increases.
3) The original use of oil change, dry change will affect the noise of the transformer. The reason is that the oil transformer is relatively small, and there is a leak chamber and a leak hole, the transformer is like a sound box.
█Solution:
A few sound-absorbing materials can be properly added indoors.
Bus bridge vibration problem
█ Reason: bus vibration due to magnetic leakage due to high current passing through side by side bus. The vibration of bus bridge will seriously affect the noise of the transformer, so that the noise of the transformer increases more than 15dB, it is difficult to judge, the general user and installation unit will be mistaken for the noise of the transformer.
█ Judgment method:
1) Noise changes with load size.
2) use a stick to push the busbar bridge, if the noise changes, it is considered that the busbar bridge is in resonance.
3) The bus vibrates in the bridge, and it is useless to use the wooden stick. Need to open the bus bridge cover plate, check whether the bus is fixed.
█ Solution:
1) It is mainly the condition of destroying the resonance of the bus bridge, tightening or loosening the derrick screw.
2) Open the cover of the bus bridge and fix the bus.
3) Low-voltage outlet adopts soft connection.
4) Please solve the busbar bridge manufacturers.
The transformer core is self-resonant
█ Reason: there is electromagnetic attraction caused by magnetic leakage between the joint and lamination of silicon steel sheet.
█ Judgment method:
1) Transformer noise is large, normal noise is mixed with other noise.
2) Transformer noise into waves.
█ Solution:
1) Tighten the screws on the transformer, including the two ends of the clamp screws, threading screws, cushion block pressure nail wire.
2) Add shockproof rubber pad under transformer trolley to solve part of the noise.
The transformer coil is self-resonant
█ Reason: vibration of winding is caused by magnetic leakage caused by load current when there is load current in winding
█Judgment method:
1) Transformer noise is large, noise is low.
2) When the load of the transformer reaches a certain level, noise begins to appear, sometimes there will be sometimes no phenomenon.
█ Solution:
1) Press the oncomelania screw with the pad once to increase the axial compression force of the coil.
2) Loosen all the nail screws of the cushion block, loosen all the bolts on the copper bar of the outgoing line and the copper bar of the neutral line, shake the low-voltage coil, shift the high-voltage coil by 3-5 mm, and then tighten all the bolts.
The nature of the load
█Cause: the transformer voltage waveform distortion (such as resonance phenomenon), noise.
█ Judgment method:
1) Noise in addition to the noise of the transformer itself, but also mixed with "gurgling, gurgling" noise.
2) In the process of operation, there will be a sudden increase in transformer noise, and soon return to normal.
3) Check whether there are rectifier equipment and frequency conversion equipment in the load.
█ Solution:
Users may consider installing harmonic reduction devices.
