The varistor is a voltage-limiting protection device. Utilizing the nonlinear characteristics of the varistor, when overvoltage occurs between the two poles of the varistor, the varistor can clamp the voltage to a relatively fixed voltage value, thereby protecting the subsequent circuit. The main parameters of the varistor are: varistor voltage, current capacity, junction capacitance, response time, etc.

　　The response time of the varistor is ns level, which is faster than the air discharge tube and slightly slower than the TVS tube. Generally, its response speed can meet the requirements for over-voltage protection of electronic circuits. The junction capacitance of a varistor is generally in the order of hundreds to thousands of Pf. In many cases, it is not suitable to be directly used in the protection of high-frequency signal lines. When used in the protection of AC circuits, its large junction capacitance will increase leakage. Current needs to be fully considered when designing protective circuits. The flow capacity of the varistor is larger, but smaller than that of the gas discharge tube.

　　The biggest feature of the varistor is that when the voltage applied to it is lower than its threshold "UN", the current flowing through it is extremely small, equivalent to a closed valve. When the voltage exceeds UN, its The resistance becomes smaller, which causes the current flowing through it to surge without much change in the impact on other circuits, thereby reducing the impact of overvoltage on subsequent sensitive circuits. Using this function, abnormal overvoltage that often occurs in the circuit can be suppressed and the circuit can be protected from overvoltage damage.

　　Nanjing Huaju Electronics Co., Ltd. is a well-known domestic R&D and production enterprise of sensitive components. In some industrial situations, due to voltage instability and high-voltage and high-energy induced voltage and current generated at the moment of power outage of inductive loads, ordinary varistors are damaged, exploded and burned. , thus causing damage to the circuit board, causing damage to the equipment, affecting the customer's production and the quality of the equipment manufacturer's products and the manufacturer's reputation. Without solving this problem, Huaju Electronics has launched the MYFBZR series of varistors with flame retardant and explosion-proof functions. This product is aimed at the shortcomings of the current surge protectors on the market, which are not very safe and still have the risk of explosion and burning. This product provides a safe lightning protector that encapsulates the varistor in a sealed shell. In the body, it plays the role of flame retardant and explosion-proof, making it safer to use. It has achieved good results and economic and social benefits in some industrial control fields. For example, in the field of servo drives and industrial inverters. In the field of industrial power supply or other frequently started or speed-regulated high-power industrial equipment. It is also widely used in the field of consumer appliances, such as refrigerator compressors, variable frequency air conditioners, etc.

　　main feature:

　　1. Sealing the varistor in the shell and isolating it from the outside air effectively prevents burning and explosion when the lightning arrester breaks down;

　　2. Fill the inside of the shell with quartz sand and epoxy resin to prevent explosion at the moment of breakdown and also have a good flame retardant effect;

　　3. The high-grade fireproof material shell and multiple fireproof and explosion-proof structures can fundamentally prevent the damage to electrical appliances when the lightning arrester burns or explodes.

　　3. Model name, appearance structure and dimensions:

Table 1: Overall dimensions

Exterior	size	MYFB10D	MYFB14D	MYFB20D
	L±0.5	15.5	20.0	26.0
	W±0.5	11.5	12	14.5
	H±0.5	19.0	25.0	30.5
	A±0.3	7.5	7.5	10.0
	d±0.02	Φ0.8	Φ0.8	Φ1.0
	B±0.3	2.3
	Fmin	3.5

Table 2

Variety Rating

Table 3: Specifications and models　

Table 3: Specifications and models

The company can also produce varistors with higher voltages according to customer requirements. Currently, the highest varistor voltage the company can produce is 2700V.