Purpose of testing transformer DC resistance:1. Check the welding quality of the winding joints and whether there is a turn to turn short circuit in the winding;2. Check whether the contact between each position of the on-load tap changer is good, and whether the actual position of the tap changer…

1. SecurityThe most important reason for conducting insulation testing is to ensure public and personal safety. By conducting insulation tests on disconnected current carrying conductors, grounding conductors, and waiting to be grounded conductors, the possibility of fire caused by short circuits can be eliminated.2. Extend equipment lifeInsulation testing is also…

In recent years, the incidence of electrical fires has always accounted for about 21% of the total number of fires, and the causes of electrical fires include equipment aging, short circuits, overload, poor contact, etc. Among them, electrical equipment aging is the main culprit. Therefore, in order to keep electrical…

The AC/DC voltage divider is used in power systems and electrical and electronic equipment manufacturing departments to measure power frequency AC high voltage and DC high voltage. It is a high voltage measurement device with impedance capacitance equipotential shielding and voltage divider. Mainly used for measuring pulse high voltage, lightning…

1、 The reasons for the increase in no-load loss and no-load current of transformers include:① Poor insulation between silicon steel sheets.② There is a short circuit between a certain part of the silicon steel sheet in the magnetic circuit.③ The insulation of the core bolts or pressure plates, upper yoke…

1、 Reasons for Short Circuit in Dry Type Transformers① Mechanical factorsLooseness of dry-type transformer components or incomplete plug insertion may cause short circuit faults. In addition, it may also cause damage to the insulation system of the transformer during transportation or installation, leading to the occurrence of short circuits.② Insulation…

1. Firstly, we need to select testing equipment with appropriate capacity. If the capacity of the testing equipment is insufficient or too large, it will affect on-site testing.2. The impact of altitude on testing requirements:As the altitude increases, the spatial density decreases, the average free travel of electrons in the…

1. The impact of weatherIn high humidity conditions, the corona loss of the leads greatly increases, while the interference of the surrounding electromagnetic field also increases, resulting in a decrease in the Q value.When the temperature is high during the experiment, the equivalent resistance of the circuit greatly increases, thereby…

The detection signal generated by partial discharge is very weak, only at the level of microvolts. In terms of numerical value, it is easy to be submerged by external interference signals. Therefore, it is necessary to consider suppressing the influence of interference signals and take effective anti-interference measures.The suppression methods…

1、 Sources of Partial Discharge InterferenceThe generalized partial discharge interference refers to not only the interference that enters the monitoring system through the current sensor along with the partial discharge signal, but also the interference that affects the monitoring system itself, such as grounding, shielding, and interference caused by improper…