Distribution transformer fault detection and processing method - Database & Sql Blog Articles

Probe domestic switch needle KG-300K needle head diameter is 3.0mm normally open switch needle

Shunuo varistor / ESD varistor / product complete / Sunlord first-class agent

TP-IP4220CZ6 5V 0.35PF breakdown voltage 6V SOT

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First, the lead part failure detection method: the three-phase DC resistance unbalance rate is much more than 4% or a phase is not at all.
Treatment method: The core should be inspected to determine the fault location, and the poor contact can be re-polished. Re-welding for poor soldering. Insufficient welding surface should be increased. If the lead cross section is insufficient, it should be replaced (increased) to meet the demand.
Second, tap changer fault detection method: measure different split DC resistance, if it is completely unsuccessful, it means that the switch is burnt; if a tap direct resistance is unbalanced, it means that the contacts are burned individually; the burnt smell is heavier, indicating overheating or arcing .
Treatment method: The core should be inspected. If the switch contacts only have overheating, poor contact or slight arcing, they can be removed and reused after inspection. If the burn is severe or the contact between the contacts is grounded, a new switch should be replaced. When the contact is discharged to the ground, it may cause deformation of the high-voltage coil regulating section, and the coil should be repaired or re-wound (replaced).
Third, the coil failure detection method: usually occurs in the coil failure oil storage cabinet oil injection, the box expansion drum, oily eschar. The insulation resistance and DC resistance can be measured, the insulation resistance is “zero”, and the DC resistance is increased and unstable.
Treatment method: Check the core to determine the fault condition. If the damage is minor, repair it. If the fault is serious, consider replacing the coil. For the oil storage cabinet to be tightly sealed, technical transformation should be carried out.
Fourth, the insulation drop detection method: the transformer is regularly used for insulation resistance and oil test. If the measured value changes greatly or is lower than the requirements of the Regulations, it can be determined that the transformer is damp or the oil insulation resistance is decreased.
Treatment method: The insulation resistance of the transformer should be completely dry, and the oil insulation should be changed to oil or filter. The transformer should be sealed tightly and the moisture absorber should be repaired.
5. Iron core failure detection method: measure the insulation resistance of the core screw, if it is less than 10 megohms, it should be overhauled.
Treatment method: After the core is lifted, the damaged core screw is taken out and the insulation is replaced.