Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

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

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

Photocoupler

A voltage transformer, also known as a potential transformer (PT), is an essential device used to step down high voltages to a lower, manageable level while maintaining the same phase relationship with the original voltage. Its working principle, construction, and wiring method are similar to those of a regular transformer, but it has a much smaller capacity—typically just a few tens or hundreds of volts. The main purpose of a voltage transformer is to reduce the high voltage by a specific ratio so that the low-voltage side can accurately reflect changes in the high-voltage side, making it easier to measure and monitor high voltages. Additionally, the voltage transformer provides electrical isolation between the primary and secondary circuits, which enhances safety for both personnel and equipment. The standard secondary voltage of a voltage transformer is usually 100V, which allows for standardized measurement instruments and protective relays. This standardization ensures compatibility and accuracy across various applications. However, if the secondary winding of a voltage transformer becomes short-circuited, it can lead to significant issues. Due to the low internal impedance of the transformer, the primary side behaves like a constant voltage source. If the secondary side is shorted, a large current will flow through the secondary coil, potentially causing overheating, insulation failure, and even a second breakdown. This not only damages the transformer but can also result in incorrect operation of protective devices and meters, leading to system instability. A loss of voltage from the transformer can cause distance protection and other voltage-dependent protection systems to malfunction. It may also result in meters showing no readings, which can compromise the overall safety and reliability of the electrical system. Therefore, it is crucial to avoid short-circuiting the secondary side of a voltage transformer at all times.