In daily life and work, we often use 220V surge protectors to protect various electrical equipment from instantaneous high-voltage shocks. But did you know that not everything can be plugged into it? If some items are plugged in rashly, it will not only damage the surge protector but may also cause safety accidents. In addition, what is the working principle of the 120V surge protector, which is similar to the 220V surge protector? Let’s learn more about it below.
Items that must not be plugged into a 220V surge protector
Loads exceeding its rated current and voltage:
220V surge protectors are mainly used to limit transient overvoltages, and they cannot bear normal working loads. Connecting a load that exceeds its rated current and voltage will cause overheating and damage to the internal components of the surge protector, and even cause safety accidents such as fire.
Non-standard plugs or wires:
If a non-standard plug or wire is used to plug into a 220V surge protector, it may cause poor contact, arcing, and overheating, increasing safety risks. At the same time, wires that do not meet the specifications may not withstand the large current that the surge protector may generate when working, causing line failures.
Internal circuits of other electronic devices or devices that are not electrically isolated:
Directly plugging the internal circuits of other electronic devices into a surge protector may destroy the original circuit structure and electrical performance of the device, causing damage to the device. Moreover, if the connected device is not electrically isolated, faults or interference inside the device may be introduced into the 220V surge protector, affecting its normal operation.
Working principle of 120V surge protector
Normal working state: When there is no surge, the nonlinear elements inside the 120V surge protector, such as varistors, gas discharge tubes, or semiconductor devices, are in a high impedance state, showing very high resistance to the normal 120V AC voltage. Almost no current passes through, which is equivalent to an open circuit and will not affect the circuit’s normal power supply.
Response when a surge occurs: When a transient overvoltage occurs in the line, such as a surge voltage generated by lightning strikes, grid operations, etc., exceeds the limit value of the surge protector, the nonlinear elements inside it will respond quickly.
Recovery after a surge: When the voltage returns to normal levels after a surge, the nonlinear elements inside the surge protector will quickly return to a high impedance state, stop discharging current, and become equivalent to an open circuit again without affecting the system’s normal power supply, waiting for the next surge to arrive.
Knowing what not to plug into a 220V surge protector can prevent us from damaging equipment or causing safety hazards due to incorrect operation. At the same time, understanding the working mechanism of a 120V surge protector can help us better understand its key role in protecting electrical equipment from surge hazards.
In practical applications, whether choosing a surge protector or connecting electrical equipment, safety, and correct operation are always the primary considerations.
This is not only related to the service life of the equipment but also to our personal and property safety. I hope that through this knowledge, everyone will be more comfortable when facing surge protection equipment and related operations.
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