• Follow us
Home > News > Content
Insulation Protective Box Overview
Oct 09, 2017

Insulation protective box overview.

The circuit breaker protects the circuit breaker and the leakage protector. Circuit breaker: circuit breaker is to control the electrical circuit of the switch, if the air for the arc medium called air circuit breaker (switch), if the sf6 gas for the arc medium called sulfur hexafluoride circuit breaker (switch). The circuit breaker is normally rated at the rated current (load) and is used as the main switch for the electrical circuit.

Leakage protector and leakage protection switch: protective box When an air switch with leakage protection function, called the leakage protection switch. If it is an electrical device used only for leakage protection, it is called a leakage protector. Leakage protector, because it does not manually turn off and close the body.

The circuit breaker is mainly composed of plastic shell, operating mechanism, contact system, interrupter, release, zero sequence current transformer and test device.

The principle of determining whether or not to leak is based on the leakage protector, which detects "inflows" and "outflows" for the power supply, since the current on the line of fire is equivalent to the outflow point of the power source and the current in the neutral line is In the power supply current "inflow" point, the line is normally no leakage, the incoming and outgoing power supply current value of the same size, the opposite direction, but when the circuit leakage when the zero line current back to the power supply current should be less than from the power into the electricity Circuit current value, up to 30mA when the protector will action, while cutting zero, FireWire. The current flowing into and out of the switch must be equal, otherwise it is judged to be leaking. protective box When the leakage current reaches and exceeds a certain degree, the protection action - trip. Determine the threshold can be set, because the circuit is designed. Only when the application according to different occasions, the use of different sensitivity of the protector. The residual current is the vector sum of the instantaneous value of the current instantaneous value of the main circuit (zero sequence transformer) of the residual current action protection device. The residual current is the current leakage of the phase to the single phase line; Three-phase line, the residual current is the instantaneous value of each phase current vector sum, with its effective value.

Leakage protector: Leakage protector is a protection appliance that detects the size of the phase-to-earth leakage or electric shock current that occurs within the protected grid and acts as an action trip signal and completes the action trip task. In the low-voltage power grid where the leakage protector is installed, under normal circumstances, the phase-to-ground leakage current (which is unbalanced leakage current in the three-phase grid) is small, and the operating current value of the leakage protector is not reached. protective box Leakage protector does not move. When the leakage occurs within the protected power grid or personal shock and other failures, through the leakage protection device to detect the current component to its leakage or electric shock action current value, the leakage protection device will occur when the action trip to control the main Circuit switch action trip, cut off the power, so as to complete the task of leakage or electric shock protection.

Leakage circuit breaker: (commonly known as leakage switch) are electromagnetic and electronic two, its working principle for the detection of residual current, the residual current value and the remaining action is the value of the flow, when the residual current exceeds the value of the break protect the circuit. It consists of residual current detection system, current transformer, high sensitivity trip mechanism, protective box test circuit, reset handle operation mechanism and so on. Its characteristics for the high sensitivity, accurate action, high reliability. Currently the market supply of leakage circuit breaker is the vast majority of electronic, such as ZLl8, DZl33, DLK, DZL30-32 and so on. DZL18, DZL33, DLK these three kinds of electronic leakage circuit breaker in addition to the role of personal shock protection, but also has the role of over-voltage protection, but does not have the role of overload protection, so the choice of such leakage circuit breakers, The

1, the structure is different; leakage switch by the switch device, leakage release and zero sequence current transformer, and low-voltage circuit breaker by the contact, arc device, operating mechanism and protection devices and other components.

2, the role of different; leakage switch only to protect the non-leakage; and low-voltage circuit breaker can not only connect and break the normal load current and overload current, protective box but also can be connected and breaking short-circuit current switching devices. Low-voltage circuit breaker in addition to the role of control in the circuit, but also has a certain protection, such as overload, short circuit, undervoltage and leakage protection. Low-voltage circuit breakers can be manually operated directly and electrically operated, or remotely operated remotely.