Jie Yamin resistor has been in detailed to approach the use point in protection
[introduction] press protection too quick the use principle of resistor is receive in its be protected after equipment, what cannot affect facility is normal move, carry out instantaneous effectively to press protection too to equipment again.
Press protection too quick the use principle of resistor is receive in its be protected after equipment, what cannot affect facility is normal move, carry out instantaneous effectively to press protection too to equipment again. For this, besides press protection too quick outside the technical parameter of resistor, consider the following issues even when choosing actually:
Press protection too quick does resistor use a point one: ? ≡ of cultivate of naphthalene of evil spirit?
Press protection too quick the is used in wiring surge of the;3kA on the protection that resistor can use in commutator of silicon controlled rectifier is absorbed go up of;5kA use in the overvoltage to be struck by lightning and electronic equipment to absorb on of;10kA use on the protection to be struck by lightning. Press latter, commonly used and integrated wave (the internal resistance of the generator of voltaic wave; that 8/20μs produces when the short circuit of voltage wave; that 1.2/50μs produces when generator open a way is outputted is outputted comes for 2Ω) the ability that online assessment equipment defies surge of be struck by lightning is disturbed. When 4kV experiments, the biggest electric current that protector absorbs can amount to the 2kA; experiment to 6kV, the maximum that absorbs electric current is 3kA. But when choosing actually, still ought to increase place choosing to press protection too appropriately quick of resistor shed a capacity.
Press protection too quick does resistor use a point 2: ? Escape elaborate of bits accept ?
Press protection too quick resistor has problem of an inherent capacitance, mix according to over all dimension nominal of voltage different, its value is in hundreds to thousands of PF between. Press protection too quick the inherent capacitance of resistor decided it does not suit to be used below high frequency circumstance, the normal moving; that can affect a system otherwise suits to be used in labour frequency system, if use as,power source enters the protection of the line, protection of commutator of silicon controlled rectifier to wait.
Press protection too quick does resistor use a point 3: ? ≡ of few of aunt Lu Miao?
Had considered press protective pressing quick resistor is pressed actually quick voltage and nominal the deviation between voltage (Lv of take an examination is nominal the 1.1~1.2 of voltage times) , the fluctuant range with likely voltage of the power source in alternating current road (should consider to be rated voltage, so, should choose pressure quick voltage is rated voltage 2.2~2.5 of times press protection too quick resistor.
Press to choosing to press protection quick for resistor, what target must consider? To signal transmission line, undertake ESD defends, beard consideration:
(1) presses protection too quick voltage of the biggest job is more than resistor; of circuit job voltage
(2) presses protection too quick photograph of transmission rate of resistor capacitance and signal matchs, press protection too namely quick resistor is transmitted in signal when, do not have attenuation to signal
(3) presses protection too quick resistor is able to bear or endure ESD ability and whole confidential request correspondence.
To road of power supply cord, undertake inductive overvoltage, operation overvoltage defends, beard consideration:
(1) presses protection too quick voltage of the biggest job is more than resistor; of circuit job voltage
(2) presses protection too quick the electric current of the greatest peak value of resistor, energy is able to bear or endure amplitude of the inductive overvoltage that the quantity must be more than the likelihood in circuit to appear, operation overvoltage. Below the condition that in position of circuit structure, space, design cost allows, choose capacitance as far as possible the product with big or large size.