Summer arrived, the dry transformer by rain erosion is more, the perennial rain for dry transformer corrosion is relatively strong. Once a lot of dry type transformer is into the water, there will be a short circuit phenomenon, leading to dry type transformer can not work, and some even will have a fire. There will be a lot of performance when the dry transformer is in the water. These performances of the dry transformer should be carefully grasped. Only words can be used to solve the fault. What is the main performance of the dry-type transformer in rainwater entry?
1. Bad sealing of casing top connecting cap.
When the sealing of the connecting cap is not good, the water enters the winding insulation along the lead wire, causing a breakdown accident. The main reasons for the poor sealing of the casing end are unreasonable structure and incorrect installation of the rubber pad.
Two, in the maintenance of damp
When the dry-type transformer hanging cover is overhauled, the body is exposed to the atmosphere. When the relative humidity of the air is large, the insulation will absorb the moisture in the air. This process starts with the top layer of insulation, and the greater the relative humidity and the longer the time, the deeper the water will penetrate.
Three, the cooler brass tube is broken
According to the regulations, the cooler should be done before the installation of leak test, in order to detect the cooler rupture defects. Failure to do so may result in a breakdown of insulation. For example: a 150MVA, L10KV power dry-type transformer, in the operation of light and heavy gas protection action trip, explosion-proof simple oil injection. Through the check of the hanging cover, it was found that 24 lines in the lower part of A-phase high-voltage winding were burnt out, and 4 short circuits were found. The hole of the two fluted reached 100mm, which was caused by the broken copper pipe of the cooler and the water entering the dry-type transformer.
Dry type transformer into the water of the phenomenon is more, the dry type transformer into the water to stop the run dry type transformer, then fix the breakdown, so safe use, dry type transformer can continue otherwise dry type transformer can appear all kinds of fault, dry type transformer into the water should not be ignored, therefore, has to be seriously rise!
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