What Cause Oil Level of Generator Transformer too High and too Low

In our actual operation process, when using diesel generator, the oil level of diesel generator transformer is often too high and too low due. Why? Today Jiangsu Starlight company answers for you.

1. The oil level is too high.

The oil level is higher than the oil level line due to the increase of oil temperature. Sometimes the oil level reaches the top line or the oil level cannot be seen. The reason is as follows:

The operation of the transformer cooler is abnormal, which causes the temperature of the transformer oil to rise and the oil to expand, resulting in the oil level to rise. The oil level of the transformer is much higher when refueling. Once the ambient temperature rises, the oil level will be too high. If the oil level is too high, which caused by the abnormal operation of the cooler. Check whether the surface of cooler is blocked by ash and whether the upper and lower valves of oil pipe are opened. Check whether the pipeline is blocked and whether the fan and submersible pump operate normally and reasonably. And check whether the temperature of cooling medium is suitable and the flow rate is sufficient.

If the oil level is too high due to excessive oil filling, we should drain the oil to a proper height. If the oil level cannot be seen, it should be judged that the oil level is indeed higher than the oil level line, and then drain the oil to a proper height. 

2. The oil level is too low.

When the oil level of the transformer is lower than the oil level corresponding to the oil temperature at that time. If the oil level is below the low oil level line or cannot be seen, it shall be judged that the oil level is too low. The reason is that:

Oil leakage of transformer.

The original oil level of the transformer is not high. In case of sudden decrease of transformer load or external environment temperature, the oil level is too low. When the oil of the strong oil water-cooled transformer flows into the oil cooler for a long time, this also causes the oil level too low. Low oil level will cause light gas protection action. If it is float relay, it will also cause heavy gas protection trip. In case of serious oil shortage, the transformer core and winding will be exposed to the air. This is not only susceptible to moisture, but also reduces the insulation and may cause insulation breakdown. Therefore, if the oil level of the transformer is too low or the oil level is reduced, make up the oil to the normal level as soon as possible.

In addition to the problem of too high or too low oil level, false oil level may be encountered.

3. False oil level.

The cause of false oil level may be:

When the non capsule sealed conservator oil gauge tube is blocked. When the respirator is blocked or the explosion-proof pipe air hole is blocked, the false oil level will appear. When there is a certain amount of air in the encapsulated conservator, capsule obstructed breathing, unreasonable position of capsule and rupture of capsule bag, it also causes false oil level.

Therefore, during the treatment, the heavy gas protection should be removed first.

If the oil level of the generator transformer is abnormal, find out the cause in time, remove the fault and ensure the normal operation of the unit.

If the oil level is obviously reduced due to serious oil leakage, it is forbidden to change the gas protection from trip to signal, should eliminate oil leakage and make oil level return to normal. If there is a large amount of oil leakage and the oil level drops below the gas relay or continues to drop, the transformer shall be stopped immediately. Before the treatment, the heavy gas protection should be removed first.

When the generator transformer is running, it is necessary to maintain the normal oil level. The operator on duty shall check the indication of the oil level gauge on time. When the oil level is too high (such as in summer), drain the oil in time. When the oil level is too low (such as in winter), make up the oil in time to maintain the normal oil level and ensure the safe operation of the transformer.

The improper oil level of transformer of diesel generator set has a great influence on the unit. So we must pay attention to the problem.

Based on the above introduction of three abnormal oil levels by Jiangsu Starlight company, users should be able to find the importance of normal oil level of transformers of diesel generator. Therefore, Starlight Power reminds the user to keep the oil level of diesel generator normal. If the oil level is too high or too low, do not panic. Check and analyze the cause of the situation in time and solve it correctly.