CN206489240U - A kind of device for being used to detect DC relay coils from parallel connection of coils diode - Google Patents
A kind of device for being used to detect DC relay coils from parallel connection of coils diode Download PDFInfo
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- CN206489240U CN206489240U CN201720144270.9U CN201720144270U CN206489240U CN 206489240 U CN206489240 U CN 206489240U CN 201720144270 U CN201720144270 U CN 201720144270U CN 206489240 U CN206489240 U CN 206489240U
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Abstract
The utility model discloses a kind of device for being used to detect DC relay coils from parallel connection of coils diode, including power supply, first resistor, main control unit, drive circuit, switching relay and follower；The positive pole of the power supply switches the first leading-in end of relay by being connected after first resistor, and the negative pole of the power supply is directly connected to switch the second leading-in end of relay, and relay coil parallel diode is connected between the exit of switching relay；The input of the follower is connected to the sample point between first resistor and the first leading-in end for switching relay, the output of follower is connected to the input of main control unit, the output of main control unit is connected to the input of drive circuit, and the output of drive circuit is connected to the coil of switching relay.The utility model can rapidly determine the state (correct, in parallel reverse, short circuit or leakage parallel connection in parallel etc.) of relay coil parallel diode, test accurate the characteristics of fast with test speed automatically.
Description
Technical field
The utility model is related to relay test technical field, more particularly to a kind of to be used to detect DC relay coil
The device of parallel diode.
Background technology
Relay is that, when input quantity reaches rated condition, one or more output quantity produces first device of predetermined transition
Part.For electromagnetic relay, can simply it be interpreted as：Input apply as defined in electric signal, its output end be switched on or switched off by
Control a kind of switch of circuit.
Because the coil of relay is inductive load, when disconnecting relay coil loop, the energy in coil is stored in
Overvoltage can be produced in switch both sides.The peak value of the overvoltage even can reach several KV, and turn-off speed is faster, overvoltage
It is higher, will very likely breakdown failure if the pressure-resistant of the semiconductor element in control coil loop is not high enough to.Negative peak electricity
Pressure is conducted along power line, can also cause serious electromagnetic disturbance.
In order to solve it is above-mentioned due to relay coil the problem that, prior art is typically in parallel in relay coil
Diode (as shown in Figure 1), when relay coil dead electricity moment, coil two ends will produce a self-induction high voltage, entail dangers to
The safety of some elements of electronic circuit, due to relay coil parallel diode, induced-current will flow through consumption from diode
Fall.
But, in relay coil parallel diode, it should be noted that relay pin direction, when parallel diode is connected just
When really (as shown in Figure 2), circuit when parallel diode connection is reverse (as shown in Figure 3), can cause circuit with normal work
Cisco unity malfunction, and can puncture diode D, triode Q1.Thus, after relay coil parallel diode, just need
Relay coil parallel diode is detected.
In the prior art, the detection to diode generally uses universal meter, and Test Diode is carried out using universal meter：
Open-circuit voltage 2V, short circuit current flow ＜ 0.6mA, on the market most short circuit current flow be substantially distributed in 0.4~0.5mA；Diode
Tube voltage drop：Silicone tube 0.7V, germanium tube is 0.3V.Therefore, if testing simple diode with universal meter, detection means is enough.But
It is that after diodes in parallel is to relay coil, the resistance sizes of coil directly affect test result, when short circuit current flow is
0.4mA, coil resistance ＜ 1.7k Ω, universal meter test will can not distinguish that diode is forward and reverse, when short circuit current flow be 0.5mA,
Coil resistance ＜ 1.4k Ω, universal meter test equally can not distinguish that diode is forward and reverse, when short circuit current flow is 0.6mA, coil
Resistance ＜ 1.1k Ω, universal meter test is also that can not distinguish that diode is forward and reverse.At present, the coil resistance of existing relay
Scope about in 2~50000 Ω, therefore, relay coil parallel diode can not be accurately detected using above-mentioned detection mode
Situation.For coil resistance ＞ 2K Ω, that is, enable test, it is also desirable to artificial to judge positive direction, it is necessary to positive test
Once, once, test process needs to read the measured value of universal meter negative testing, and≤0.7V is judged as forward direction, conversely, sentencing
Break to be reverse, this detection mode test speed is slow, and people labour union produces fatigue, causes erroneous judgement.
Utility model content
The purpose of this utility model is to overcome the deficiency of prior art to be used to detect DC relay coil there is provided one kind
The device of parallel diode, the state that relay coil parallel diode can be rapidly determined automatically is (in parallel correct, in parallel
Reversely, short circuit or leakage parallel connection etc.), test accurate the characteristics of fast with test speed.
The utility model solves the technical scheme that its technical problem used：One kind is used to detect DC relay coil
The device of parallel diode, including power supply, first resistor, main control unit, drive circuit, switching relay and follower；It is described
The positive pole of power supply switches the first leading-in end of relay by being connected after first resistor, and the negative pole of the power supply is directly connected to switching
Second leading-in end of relay, relay coil parallel diode is connected between the exit of switching relay；It is described to follow
The input of device is connected to the sample point between first resistor and the first leading-in end for switching relay, and the output of follower is connected to master
The input of unit is controlled, the output of main control unit is connected to the input of drive circuit, and the output of drive circuit is connected to switching relay
Coil.
A second resistance is also connected between the input of the follower and the sampled point.
Described drive circuit includes 3rd resistor and the first triode, the positive pole pin of the coil of the switching relay
The preset positive potential in circuit is connected to, the negative pin for switching the coil of relay is connected to the colelctor electrode of the first triode, the
The grounded emitter of one triode, the base stage of the first triode connects one end of 3rd resistor, and the another of 3rd resistor is connected to
The output of main control unit.
First triode is NPN type triode.
Coil one first diode also in parallel of the switching relay, the negative pole connection switching of first diode after
The positive pole pin of the coil of electrical equipment, the negative pin of the coil of the positive pole connection switching relay of the one or two pole.
The exit of the switching relay includes the first exit, the second exit, three terminal and the 4th and drawn
End, the first leading-in end switching of the switching relay is connected between the first exit and the second exit, switches relay
The second leading-in end switching be connected between three terminal and the 4th exit, after the first exit connects with the 4th exit
Connect the first pin of the relay coil to be measured in relay coil parallel diode, the second exit and three terminal phase
The second pin of the relay coil to be measured in relay coil parallel diode is connected after connecing.
When being detected using a kind of device for detecting DC relay coils from parallel connection of coils diode of the present utility model,
It comprises the following steps：
Main control unit exports low level, and switching relay does not work, and power supply is by switching after relay to relay coil
Parallel diode exports forward voltage；
Main control unit gathers the current potential of sampled point by follower for the first time, and the potential value gathered to the first time enters
Row judges, when the potential value of the collection for the first time is substantially zeroed, judges parallel diode for breakdown conditions, terminates test,
When the potential value that the first time gathers is not zero, continue next step；
Main control unit exports high level, switching relay work, and power supply is by switching after relay to relay coil simultaneously
Di- pole pipe exports backward voltage；
Main control unit gathers the current potential of sampled point by follower second, and by the potential value of first time collection and the
The potential value of secondary acquisition is judged with preset voltage threshold respectively, and is determined and di- pole according to preset condition
The state of pipe.
It is described by the potential value of first time collection and second potential value gathered respectively with preset voltage threshold
Judged, and the state of parallel diode is determined according to preset condition, be：
When first time collection potential value be more than preset voltage threshold, and the potential value gathered for the second time be less than etc.
When preset voltage threshold, judge parallel diode to be in parallel correct；
When the potential value of first time collection is less than or equal to preset voltage threshold, and the potential value gathered for the second time is big
When preset voltage threshold, judge parallel diode to be in parallel reverse；
The potential value of collection is more than preset voltage threshold for the first time, and the potential value gathered for the second time is also greater than pre-
During the voltage threshold put, judge that parallel diode is in parallel for leakage.
The preset voltage threshold is the tube voltage drop of parallel diode.
Compared with prior art, the beneficial effects of the utility model are：
The utility model is as a result of power supply, first resistor, main control unit, drive circuit, switching relay and follows
Device constitutes the device for detecting DC relay coils from parallel connection of coils diode, and the positive pole of power supply passes through and connected after first resistor
Switch the first leading-in end of relay, the negative pole of the power supply is directly connected to switch the second leading-in end of relay, relay line
Circle parallel diode is connected between the exit of switching relay；The input of the follower be connected to first resistor with switching after
Sample point between first leading-in end of electrical equipment, the output of follower is connected to the input of main control unit, the output of main control unit
The input of drive circuit is connected to, the output of drive circuit is connected to the coil of switching relay.The utility model passes through the device energy
(correct, in parallel reverse, short circuit or leakage in parallel are in parallel for the enough automatic state for rapidly determining relay coil parallel diode
Deng), test accurate the characteristics of fast with test speed.
The utility model is described in further detail below in conjunction with drawings and Examples；But a kind of use of the present utility model
Embodiment is not limited in the device of detection DC relay coils from parallel connection of coils diode.
Brief description of the drawings
Fig. 1 is the schematic diagram of the relay coil parallel diode of prior art；
Fig. 2 is the relay coil parallel diode schematic diagram in the right direction of prior art；
Fig. 3 is the reverse schematic diagram in relay coil parallel diode direction of prior art；
Fig. 4 is the theory diagram of embodiment device of the present utility model；
Fig. 5 is that embodiment device of the present utility model is connected the electricity of (forward direction be connected) with relay coil parallel diode
Lu Tu；
Fig. 6 is that embodiment device of the present utility model is connected the electricity of (Opposite direction connection) with relay coil parallel diode
Lu Tu.
Embodiment
Embodiment
It is shown in Figure 4, a kind of device for being used to detect DC relay coils from parallel connection of coils diode of the present utility model, bag
Include power supply 1, first resistor 2, main control unit 3, drive circuit 4, switching relay 5 and follower 6；The positive pole of the power supply 1 leads to
The first leading-in end of connection switching relay 5 after first resistor 2 is crossed, the negative pole of the power supply 1 is directly connected to switch relay 5
Second leading-in end, relay coil parallel diode 7 is connected between the exit of switching relay 5；The follower 6 it is defeated
Enter to be connected to the sample point between first resistor 2 and the first leading-in end for switching relay 5, the output of follower 6 is connected to master control
The input of unit 3, the output of main control unit 3 is connected to the input of drive circuit 4, and the output of drive circuit 4 is connected to switching relay 5
Coil.
It is shown in Figure 5, a kind of device for being used to detect DC relay coils from parallel connection of coils diode of the present utility model, electricity
The first leading-in end that source E positive pole switches relay 5 by being connected after first resistor R1 is the 3. pin, and power supply E negative pole is direct
Second leading-in end of connection switching relay 5 is the 6. pin.
The input of follower 6 is connected to first resistor R1 and switches the first leading-in end i.e. the of relay 5 3. adopting between pin
At sampling point A.
A second resistance R2 is also connected between the input of follower 6 and the sampled point A.
Main control unit uses MCU, main control unit MCU to carry AD.
Drive circuit 4 includes 3rd resistor R3 and the first triode Q1, and the positive pole pin for switching the coil JM of relay 5 connects
The preset positive potential (the present embodiment is+5V) being connected in circuit, the negative pin for switching the coil JM of relay is connected to the one or three
Pole pipe Q1 colelctor electrode, the first triode Q1 grounded emitter, the one of the first triode Q1 base stage connection 3rd resistor R3
End, the another of 3rd resistor R3 is connected to main control unit i.e. MCU output；Main control unit is that MCU carries AD.
First triode Q1 is NPN type triode.
The negative pole connection for switching coil JM also one first the diode D1, the first diode D1 of parallel connection of relay 5 is cut
The coil JM of relay positive pole pin is changed, the coil JM of the first diode Q1 positive pole connection switching relay 5 negative pole draws
Pin.
The exit of switching relay 5 is 4. pin, the second i.e. 5. pin, the 3rd extraction of exit including the first exit
7. pin and the 4th exit are the 8. pin to end i.e. the, the first leading-in end of the switching relay be the 3. pin switching be connected to the
One exit is the 4. pin and the second exit i.e. the 5. between pin, the second leading-in end of switching relay be the 6. pin switching connect
It is connected on 7. pin and the 4th exit i.e. 8. between pin of three terminal i.e., the first exit is the 3. pin and the 4th exit
The 1. pin of first pin of the relay coil to be measured in the i.e. the connection relay coil parallel diode after 8. pin connects i.e. the, the
Two exits be 5. pin and three terminal i.e. be connected after 7. pin connects in relay coil parallel diode it is to be measured after
The second pin of electric apparatus coil is the 2. pin.
Referring to shown in Fig. 4, Fig. 5, using of the present utility model a kind of for detecting DC relay coils from parallel connection of coils diode
Device when being detected, it comprises the following steps：
Main control unit MCU exports low level, and switching relay 5 does not work, and power supply E is by switching after relay 5 to relay
Device coils from parallel connection of coils diode 7 exports forward voltage；
Main control unit MCU gathers the current potential of sampled point by follower 6 for the first time, and to the current potential number of the collection for the first time
Value is judged, when the potential value of the collection for the first time is substantially zeroed, is judged parallel diode for breakdown conditions, is terminated to survey
Examination, when the potential value that the first time gathers is not zero, continues next step；
Main control unit MCU exports high level, and switching relay 5 works, and power supply E is by switching after relay 5 to relay
Coils from parallel connection of coils diode 7 exports backward voltage；
Main control unit MCU by the current potential of second of follower 6 collection sampled point, and will collection for the first time potential value
Judged respectively with preset voltage threshold with the potential value of second of collection, and parallel connection is determined according to preset condition
The state of diode.
It is described by the potential value of first time collection and second potential value gathered respectively with preset voltage threshold
Judged, and the state of parallel diode is determined according to preset condition, be：
When first time collection potential value be more than preset voltage threshold, and the potential value gathered for the second time be less than etc.
When preset voltage threshold, judge parallel diode to be in parallel correct；
When the potential value of first time collection is less than or equal to preset voltage threshold, and the potential value gathered for the second time is big
When preset voltage threshold, judge parallel diode to be in parallel reverse；
The potential value of collection is more than preset voltage threshold for the first time, and the potential value gathered for the second time is also greater than pre-
During the voltage threshold put, judge that parallel diode is in parallel for leakage.
The preset voltage threshold is the tube voltage drop of parallel diode.
It is assumed that when the coil resistance of relay is 2 Ω, parallel diode pressure drop is 0.7V, therefore, relay coil to be measured
Resistance is Rj, and test loop electric current is △ I；
R1 selection, E/ (R1+Rj) * Rj=△ V, during diode reverse, it is necessary to assure △ V ＞ 0.7V, it is assumed that E is
DC6V, Rj take 2 Ω, then △ I=0.7V/2 Ω=0.35A, △ I*Rj+ △ I*R1=E；
Calculated by formula, R1 is about 13 Ω.
Formula is constant, in test process, when E changes, as long as adjusting suitable R1, is then read again by MCU AD
Concrete numerical value △ U, by the numerical value, carry out automatic identification direction, it can be determined that four kinds of states of parallel diode：Parallel connection is just
Really, in parallel reverse, short-circuit (diode breakdown), leakage is in parallel.
When diode breakdown, no matter positive or direction, the essentially 0V that △ U are read；
When diode is forward direction, the voltage that △ U are read is diode turn-on voltage, and silicone tube 0.7V, germanium tube is 0.3V；
When diode is reverse, the voltage that △ U are read is the voltage on Rj；
When diode leaks simultaneously, the equal ＞ 0.7V of voltage that △ U are read；
In test process, as long as setting △ U bound, it is possible to judge direction, two poles of relay parallel diode
Pipe whether there is leakage and, diode whether there is punctures.Test speed is fast, and accurately.
As shown in figure 5, when main control unit MCU exports low level, switching relay 5 does not work, and current direction is：E+→
R1 → the 3. pin → the 4. 1. 2. pin → the 7. pin → the 6. pin → the E- of pin → relay to be measured of pin → relay to be measured；
In relay coil parallel diode, parallel diode is not turned on, and the current potential of A points is the pressure drop of the coil of relay to be measured, because
And the potential value gathered for the first time is more than the tube voltage drop of parallel diode, i.e. ＞ 0.7V；When main control unit MCU exports high level
When, switching relay 5 works, and current direction is：E+ → R1 → the 3. pin → the 5. 2. the pin → to be measured of pin → relay to be measured
1. pin → the 8. pin → the 6. pin → the E- of relay；In relay coil parallel diode, parallel diode conducting, A points
Current potential be parallel diode tube voltage drop, thus the potential value of second collection is less than or equal to the pipe pressure of parallel diode
Drop, i.e. ＞ 0V ,≤0.7V.
As shown in fig. 6, when parallel diode is reversed, during main control unit MCU output low levels, switching the not work of relay 5
Make, current direction is：E+ → R1 → the 3. pin → the 4. 1. 2. pin → the of pin → relay to be measured of pin → relay to be measured
7. pin → the 6. pin → E-；In relay coil parallel diode, parallel diode conducting, the current potential of A points is simultaneously di- pole
The tube voltage drop of pipe, thus the potential value of collection is less than or equal to the tube voltage drop of parallel diode, i.e. ＞ 0V ,≤0.7V for the first time；
When main control unit MCU exports high level, switching relay 5 works, and current direction is：E+ → R1 → the 3. pin → the 5. pin →
The 2. 1. pin → the 8. pin → the 6. pin → E- of pin → relay to be measured of relay to be measured；In relay coil parallel diode
In, parallel diode is not turned on, and the current potentials of A points is the pressure drop of the coil of relay to be measured, thus the current potential number of second of collection
Value is more than the tube voltage drop of parallel diode, i.e. ＞ 0.7V.
It is of the present utility model it is a kind of be used to detect the device of DC relay coils from parallel connection of coils diode, employ power supply 1, the
One resistance 2, main control unit 3, drive circuit 4, switching relay 5 and follower 6 are used to detect DC relay coil to constitute
The device of parallel diode, and power supply 1 positive pole by after first resistor 2 connect switch relay 5 the first leading-in end, it is described
The negative pole of power supply 1 be directly connected to switch relay 5 the second leading-in end, relay coil parallel diode 7 be connected to switching after
Between the exit of electrical equipment 5；The input of the follower 6 is connected between first resistor 2 and the first leading-in end for switching relay 5
Sampled point A at, the output of follower 6 is connected to the input of main control unit 3, and the output of main control unit 3 is connected to the defeated of drive circuit 4
Enter, the output of drive circuit 4 is connected to the coil of switching relay 5.The utility model can rapidly be sentenced automatically by the device
Do not go out the state (correct, in parallel reverse, short circuit or leakage parallel connection in parallel etc.) of relay coil parallel diode, with test speed
It hurry up, the characteristics of testing accurate.
Above-mentioned simply preferred embodiment of the present utility model, not makees any formal limitation to the utility model.Though
Right the utility model is disclosed above with preferred embodiment, but is not limited to the utility model.It is any to be familiar with this area
Technical staff, in the case where not departing from technical solutions of the utility model scope, all using the technology contents of the disclosure above
Technical solutions of the utility model are made with many possible variations and modification, or is revised as equivalents equivalent embodiment.Therefore,
Every content without departing from technical solutions of the utility model, according to the utility model technical spirit to made for any of the above embodiments
What simple modification, equivalent variation and modification, all should fall in the range of technical solutions of the utility model protection.
Claims (6)
1. a kind of device for being used to detect DC relay coils from parallel connection of coils diode, it is characterised in that：Including power supply, the first electricity
Resistance, main control unit, drive circuit, switching relay and follower；The positive pole of the power supply is switched by being connected after first resistor
First leading-in end of relay, the negative pole of the power supply is directly connected to switch the second leading-in end of relay, and relay coil is simultaneously
Di- pole pipe is connected between the exit of switching relay；The input of the follower is connected to first resistor and switching relay
The first leading-in end between sample point, the output of follower is connected to the input of main control unit, and the output of main control unit is connected to
The input of drive circuit, the output of drive circuit is connected to the coil of switching relay.
2. the device according to claim 1 for being used to detect DC relay coils from parallel connection of coils diode, it is characterised in that：Institute
State and a second resistance is also connected between the input of follower and the sampled point.
3. the device according to claim 1 for being used to detect DC relay coils from parallel connection of coils diode, it is characterised in that：Institute
The drive circuit stated includes 3rd resistor and the first triode, and the positive pole pin of the coil of the switching relay is connected to circuit
In preset positive potential, the negative pin for switching the coil of relay is connected to the colelctor electrode of the first triode, the first triode
Grounded emitter, the base stage of the first triode connects one end of 3rd resistor, another main control unit that is connected to of 3rd resistor
Output.
4. the device according to claim 3 for being used to detect DC relay coils from parallel connection of coils diode, it is characterised in that：Institute
The first triode is stated for NPN type triode.
5. the device according to claim 3 for being used to detect DC relay coils from parallel connection of coils diode, it is characterised in that：Institute
State coil one first diode also in parallel of switching relay, the coil of the negative pole connection switching relay of first diode
Positive pole pin, the one or two pole positive pole connection switching relay coil negative pin.
6. the device according to claim 1 for being used to detect DC relay coils from parallel connection of coils diode, it is characterised in that：Institute
Stating the exit of switching relay includes the first exit, the second exit, three terminal and the 4th exit, the switching
The first leading-in end switching of relay is connected between the first exit and the second exit, switches the second leading-in end of relay
Switching is connected between three terminal and the 4th exit, and the first exit is connected relay line after connecting with the 4th exit
First pin of the relay coil to be measured enclosed in parallel diode, the second exit is connected relay after connecting with three terminal
The second pin of relay coil to be measured in device coils from parallel connection of coils diode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720144270.9U CN206489240U (en) | 2017-02-17 | 2017-02-17 | A kind of device for being used to detect DC relay coils from parallel connection of coils diode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720144270.9U CN206489240U (en) | 2017-02-17 | 2017-02-17 | A kind of device for being used to detect DC relay coils from parallel connection of coils diode |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206489240U true CN206489240U (en) | 2017-09-12 |
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ID=59764608
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201720144270.9U Active CN206489240U (en) | 2017-02-17 | 2017-02-17 | A kind of device for being used to detect DC relay coils from parallel connection of coils diode |
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| CN (1) | CN206489240U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106680655A (en) * | 2017-02-17 | 2017-05-17 | 厦门顶科电子有限公司 | Device and method for detecting direct-current relay coil parallel diodes |
| CN115219764A (en) * | 2022-07-11 | 2022-10-21 | 上海钧嵌传感技术有限公司 | Pulse current protection circuit and method for current sensor and current sensor |
-
2017
- 2017-02-17 CN CN201720144270.9U patent/CN206489240U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106680655A (en) * | 2017-02-17 | 2017-05-17 | 厦门顶科电子有限公司 | Device and method for detecting direct-current relay coil parallel diodes |
| CN115219764A (en) * | 2022-07-11 | 2022-10-21 | 上海钧嵌传感技术有限公司 | Pulse current protection circuit and method for current sensor and current sensor |
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