Diode of follow on current is to point to retrorse paralell connection to wait for Chu Nengyuan in inductance coil, relay, silicon controlled rectifier normally two end, when occurrence mutation of the voltage in circuit or electric current, remove the diode that protects action to component of the other in circuit.

 

It is with inductance coil exemple, when there is electric current to pass in coil, its two end can have generation of inductive electromotive force. When electric current disappears, electromotive force meets its induction produce retrorse tension to the component in circuit. When the retrorse puncture voltage of component of retrorse voltage prep above, can wait for component like dynatron burned-out. If be in coil two end are retrorse and shunt-wound a diode (can string together occasionally receive) of a resistor, when the electric current in shedding coil disappears, the inductive electromotive force that coil produces can pass the return circuit that diode and coil make to be used up, assure the safety of the other component in circuit thereby.

 

To relay, because the coil of relay is a very big inductance, it can store with the form of magnetic field electric energy, suck the meeting memory is many magnetic field when closing when it so. The dynatron that should control relay by guide turn into up to when, coil can cut off the power, but right now the magnetic field in coil did not disappear instantly, this magnetic field will produce retrorse electromotive force, its voltage can be as high as 1000v, very easy puncture is like such high pressure dynatron or other circuit element. If we are in relay two end are retrorse and shunt-wound a diode (to relay, can string together on diode of follow on current normally receive a resistor in order to prevent loop electric current exorbitant) , as a result of this diode receive as it happens and direction of retrorse electromotive force to agree, such OK use up retrorse electromotive force with voltaic form, achieve protective other circuit thereby yuan the purpose of parts of an apparatus.

 

To circuit of silicon controlled rectifier, because silicon controlled rectifier regards as commonly,switch of a contact is used, if pilot is big inductance load, same meeting produces high pressure to oppose electromotive force, its principle and relay are same. Also can use diode of follow on current likewise on monitor, it is to be used on the coil of degauss relay commonly.

 

 

 

The graph gave out on the representative application circuit of diode of follow on current, among them resistor R inspects a circumstance to decide to whether need. Chu Nengyuan guide in VT when connecting, voltage is lost to go up to falling, voltaic direction from go up downward. When VT closes, chu Nengyuan medium electric current is interrupted suddenly, can produce inductive electromotive force right now, its direction is strive carries electricity changeless, always want to maintain Chu Nengyuan namely voltaic direction from on downward. After this reaction electromotive force and alternate of power source voltage are added, add in VT two end, make easily VT puncture, it is this to be able to add VD, such OK Chu Nengyuan the short circuit of inductive electromotive force of generation is dropped, achieve the goal that protects VT thereby.

 

Diode of follow on current is mixed normally Chu Nengyuan use together, its action is the mutation of electric current of the voltage in preventing circuit, provide access of bad news report for retrorse electromotive force. Inductance coil can provide persistent electricity to load through it, lest load current is choppy, have the effect of flowing electric current! In switch power source, can see one is strung by diode and resistor rise form circuit of follow on current. This circuit is as shunt-wound as transformer former edge. When switch canal closes, circuit of follow on current can release the energy that stores in transformer coil, prevent inductive voltage exorbitant, puncture switch is in charge of.

 

General choice restores diode quickly or diode of Xiao Te radical, be like FR254, FR255, FR256, FR257, 1N5204, 1N5205, 1N5206, 1N5207, 1N5208, 1N5404, 1N5405, 5406, 5407, 5408 etc.

 

 

Diode of follow on current applies in switch power source, relay normally in the circuit of circuit, silicon controlled rectifier, circuit such as IGBT, its application is very wide. Should notice when use when:

(Diode of 1) follow on current is when preventing dc coil to cut off the power, the tall voltage that generation forms from electrification situation is right relevant yuan parts of an apparatus causes damaged significant step

(The polarity of diode of 2) follow on current cannot receive a fault, will cause short circuit accident otherwise

(Diode of 3) follow on current always receives instead to volts d.c. , namely the positive electrode end that the negative pole of diode receives dc

(Diode of 4) follow on current is the job is in to on-state, be not puncture condition or condition of high speed switch