Dry-type transformer output voltage to be maintained within a range . If there is a failure, in addition to the power supply reasons, the common causes of failure are as follows:

1. winding resistance phase to phase short circuit caused. This type of failure is mostly seen in dry-type transformer overload or insulation layer reduction caused by the occurrence of turns smell short-circuit failure, dry-type transformer will have an abnormal output voltage, and sometimes there will be ultra-temperature and ringing abnormal conditions along with.

2.tap changer block position is caused by error. Tap changer is used to adjust the current, if there is a mistake in the block position, can not match the specific power supply current, will also cause the output voltage is too high or too low.

3. Three-phase load imbalance. If the dry-type transformer secondary three-phase unbalanced, will lead to dry-type transformer three-phase voltage shift, the output voltage is abnormal. In serious cases, the DC voltage rises 1.732 times.

4. Phase loss on the high voltage side. A phase loss on the high voltage side can also cause a serious imbalance in the output voltage of the low voltage side, and even lead to the destruction of low voltage equipment. There are many reasons for phase loss on the high voltage side, but it is generally due to the lack of maintenance in place, which leads to part of the wiring being burned out or the failure of the old superiors’ distribution lines.

Most of the dry-type transformer usual common problems have been listed above, so the later routine maintenance work must be done, the failure of the problem can be made in a timely manner to distinguish and repair, to prevent the entire power supply circuit has an impact on, resulting in unnecessary trouble.