Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

In practical work, insulation resistance of distribution transformers is generally measured twice: the insulation resistance between thehigh-voltage (HV) windingand thelow-voltage (LV) winding plus the transformer tank, and the insulation resistance between theLV windingand theHV winding plus the transformer tank.If both measurements yield acceptable values, it indicates that the insulation among the HV winding, LV winding, and transformer tank is qualified. If either measurement fails, pairwise

IntroductionSF6 gas is widely used as an insulating and arc-quenching medium in high-voltage and extra-high-voltage electrical equipment due to its excellent insulation, arc-extinguishing properties, and chemical stability. The insulation strength and arc-quenching capability of electrical equipment depend on the density of SF6 gas. A decrease in SF6 gas density can lead to two main hazards: Reduced dielectric strength of the equipment; Decreased interrupting capacity of circuit breakers.Additio

As the title suggests, when performing live partial discharge (PD) testing on Siemens GIS using the UHF method—specifically by accessing the signal through the metal flange of the bushing insulator—you must not directly remove the metal cover on the bushing insulator.Why?You won’t realize the danger until you try. Once removed, the GIS will leak SF₆ gas while energized! Enough talk—let’s go straight to the diagrams.As shown in Figure 1, the small aluminum cover inside the red box is typically th

Outdoor low-voltage power distribution boxes (hereinafter referred to as "distribution boxes") are low-voltage distribution equipment used in 380/220V power supply systems to receive and distribute electrical energy. They are generally installed at locations such as the low-voltage side of distribution transformers. The interior is typically equipped with protective devices like fuses, leakage protectors, and surge arresters; control devices like contactors, circuit breakers, load switches, and

CooperationSafety requires the cooperation of all workers involved.AwarenessWorkers must be aware of all safety rules and regulations.Voltage DangerTreat all voltage levels as dangerous, even if they don’t cause shock.Dead CircuitEnsure the circuit is off before starting any work.Personal Protective EquipmentUse appropriate safety gear to protect yourself.