CN110988666B - Device for detecting voltage bearing and current bearing of relay contact - Google Patents
Device for detecting voltage bearing and current bearing of relay contact Download PDFInfo
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- CN110988666B CN110988666B CN201911217984.8A CN201911217984A CN110988666B CN 110988666 B CN110988666 B CN 110988666B CN 201911217984 A CN201911217984 A CN 201911217984A CN 110988666 B CN110988666 B CN 110988666B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3277—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches
- G01R31/3278—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches of relays, solenoids or reed switches
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
Abstract
A device for detecting the voltage carried by the relay contact and switching on the carried current is provided with a voltage source, a monitoring unit, a time control cut-off unit, a tested contact K1 interface and a load unit. The invention has the advantages that 1, the number of detection loops required can be reduced, namely, the same detection loop can finish the detection of the bearing voltage and the bearing current and simultaneously can reduce the probability of manually connecting the detection loops in a wrong way; 2. the number of times of wire replacement can be reduced, and the contact to be tested can be tested only by accessing the K1 interface of the contact to be tested once; 3. the time for switching on the load current can be accurately timed, so that errors caused by manual timing are avoided; 4. the switch-on bearing current of the tested contact K1 interface can be automatically cut off; 5. a user can manually disconnect the tested contact K1 according to the current shown by the monitoring unit, and the normally open contact K3 of the contactor is ensured to be disconnected before the tested contact K1, so that the risk that the tested contact K1 bears high-energy arc discharge due to manual operation sequence reversal is avoided.
Description
Technical Field
The invention relates to the field of relay inspection, in particular to a device for detecting the voltage carried by a relay contact and switching on the carried current.
Background
The detection of the relay in the prior art needs two loops of voltage output and current output, a contact is connected into the voltage output loop when the contact is detected to bear voltage, the contact is connected into the current output loop when the contact is detected to be connected with bearing current, and the contactor is manually operated to disconnect the current through manual timing. The disadvantages of this detection method are as follows:
1. the secondary wiring is required to realize the switching of the voltage and current detection loops, so that the switching is easily influenced by human factors, such as wrong connection of the voltage and current detection loops.
2. The contactor is manually operated to cut off the current through manual timing, only second-level operation can be realized, the timing precision is limited by the reaction speed of an operator, actually, the limit on current of most relay contacts can only last 200ms, manual timing is difficult to realize for short-time operation, and the contact to be measured is easily damaged due to overlong power-on time.
3. The manual operation realizes that the contactor is firstly disconnected and then the tested contact is disconnected, and once the sequence is reversed, the tested contact can bear large energy to be subjected to arc discharge so as to be damaged.
4. In order to output a large current, the current output circuit greatly reduces the power supply voltage value and the load unit capability, so that the actual power load unit cannot be simulated.
The specific reasons for the above disadvantages are:
1. the power of the testing device is too small, so that the voltage and current can not be tested by using one loop, and the actual large-scale power load unit can not be truly simulated.
2. Absent an effective time-controlled current-interrupting unit, accurate timing and automatic disconnection of the loop current before the tested contacts are opened is not possible.
Therefore, it is necessary to provide a device for detecting the voltage carried by the relay contact and the current carried by the relay contact to solve the deficiencies of the prior art.
Disclosure of Invention
The invention aims to avoid the defects of the prior art and provides a device for detecting the bearing voltage and switching on the bearing current of a relay contact. The device for detecting the voltage borne by the relay contact and the current borne by the relay contact is connected has the advantages of reducing the number of line changing times, reducing the number of detection loops, accurately timing, avoiding the damage of the contact to be detected due to high-energy arc discharge and automatically cutting off the current borne by the contact to be detected.
The above object of the present invention is achieved by the following technical measures:
a device for detecting the voltage carried by the contact of the relay and switching on the carried current is provided with a voltage source, a monitoring unit, a time control current cut-off unit, a tested contact K1 interface and a load unit.
And the voltage source provides the bearing voltage required by the contact point to be tested and provides the required switch-on bearing current for the contact point to be tested together with the load unit.
And the tested contact K1 is connected with the tested contact.
And the monitoring unit is used for monitoring the bearing voltage and switching on the bearing current.
And the time control current cut-off unit is used for timing the on-load current and breaking the current before the tested contact is cut off.
And the load unit and the voltage source together provide the required switch-on load current of the contact to be tested.
Preferably, the time-controlled current-breaking unit is provided with a contactor assembly, a time relay assembly and a switching power supply, and the contactor assembly and the time relay assembly are respectively connected with the monitoring unit, the tested contact K1 interface, the voltage source, the load unit and the switching power supply.
Preferably, the contactor assembly is provided with a contactor coil L2 and a contactor normally open contact K3, and the contactor normally open contact K3 and the contactor coil L2 are connected by magnetic coupling.
Preferably, the time relay assembly is provided with a time relay coil L1 and a time relay normally closed contact K2, and the time relay coil L1 and the time relay normally closed contact K2 are connected by magnetic coupling.
Preferably, the time relay coil L1 is connected to a contactor normally open contact K3.
Preferably, the contactor coil L2, the switching power supply and the time relay normally closed contact K2 are connected by wires.
Preferably, the closing condition of the time relay normally closed contact K2 is that the time relay coil L1 is not excited and does not reach the set time of the time relay.
Preferably, the closing condition of the contactor normally open contact K3 is excitation of the contactor coil L2.
Preferably, the monitoring unit is provided with an ammeter a and a voltmeter V.
Preferably, the load unit is a high power ripple resistor R.
One end of the interface of the contact K1 to be tested is connected with one end of the ammeter A.
The other end of the tested contact K1 interface is respectively connected with one end of a time relay coil L1 and one end of a contactor normally open contact K3.
The other end of the ammeter A is respectively connected with one end of the voltmeter V and one end of the voltage source.
The other end of voltmeter V and the other end of the voltage source are both connected to the other end of time relay coil L1.
The other end of the time relay coil L1 is connected in series with a high-power ripple resistor R and then is connected with one end of a normally open contact K3 of the contactor.
One end of the time relay normally closed contact K2 is sequentially connected in series with the switching power supply and the contactor coil L2 and then connected with the other end of the time relay normally closed contact K2.
Preferably, the timing range of the time relay coil L1 is 0.1 second to 99 hours and the time resolution is 100 milliseconds or more.
Preferably, the contactor module has a minimum breaking capacity of 30 amperes.
Preferably, the range of the voltmeter V is 600V.
Preferably, the range of the ammeter a is 100 a.
Preferably, the resistance value of the high power ripple resistor R is 8.33 ohms.
Preferably, the voltage source is an AC/DC voltage source and has a capacity greater than or equal to 7500 volt-ampere/watt.
The invention discloses a device for detecting the voltage carried by a relay contact and switching on the carried current, which is provided with a voltage source, a monitoring unit, a time control current-cut-off unit, a tested contact K1 interface and a load unit; the voltage source provides the bearing voltage required by the contact to be tested and provides the required switch-on bearing current for the contact to be tested together with the load unit; the tested contact K1 interface is connected with the tested contact; the monitoring unit is used for monitoring the bearing voltage and switching on the bearing current; the time control current-breaking unit is used for timing the on-load current and breaking the current before the tested contact is broken; and the load unit and the voltage source together provide the required switch-on load current of the contact to be tested. The invention has the advantages that 1, the number of detection loops required can be reduced, namely, the same detection loop can finish the detection of the bearing voltage and the bearing current and simultaneously can reduce the probability of manually connecting the detection loops in a wrong way; 2. the number of times of wire replacement can be reduced, and the contact to be tested can be tested only by accessing the K1 interface of the contact to be tested once; 3. the time for switching on the load current can be accurately timed, so that errors caused by manual timing are avoided; 4. the switch-on bearing current of the tested contact K1 interface can be automatically cut off; 5. a user can manually disconnect the tested contact K1 according to the current shown by the monitoring unit, and the normally open contact K3 of the contactor is ensured to be disconnected before the tested contact K1, so that the risk that the tested contact K1 bears high-energy arc discharge due to manual operation sequence reversal is avoided; 6. and truly simulating a large power load.
Drawings
The invention is further illustrated by means of the attached drawings, the content of which is not in any way limiting.
FIG. 1 is a circuit diagram of an apparatus for detecting voltage-carrying and current-carrying contact of a relay according to embodiment 1
In fig. 1, the following components are included:
a voltage source 1,
A monitoring unit 2,
A time-controlled current-cut-off unit 3,
The tested contact K1 interface 4,
A load unit 5.
Detailed Description
The technical solution of the present invention is further illustrated by the following examples.
Example 1.
A device for detecting voltage carried by a relay contact and switching on current carried by the relay contact is provided with a voltage source 1, a monitoring unit 2, a time control current cut-off unit 3, a tested contact K1 interface 4 and a load unit 5 as shown in figure 1.
The voltage source 1 provides the bearing voltage needed by the contact point to be tested, and provides the needed switch-on bearing current for the contact point to be tested together with the load unit 5.
And the tested contact K1 is connected with the interface 4 of the tested contact.
And the monitoring unit 2 is used for monitoring the bearing voltage and switching on the bearing current.
The time-controlled current interruption unit 3 times the current to be carried and interrupts the current before the contact to be measured is opened.
And the load unit 5 and the voltage source 1 are used for providing the required switch-on load current for the contact point to be tested.
The time control current-cut-off unit 3 is provided with a contactor assembly, a time relay assembly and a switching power supply, and the contactor assembly and the time relay assembly are respectively connected with the monitoring unit 2, the tested contact K1 interface 4, the voltage source 1, the load unit 5 and the switching power supply.
The contactor assembly is provided with a contactor coil L2 and a contactor normally open contact K3, and the contactor normally open contact K3 and a contactor coil L2 are connected through magnetic coupling.
Wherein, the time relay assembly is provided with a time relay coil L1 and a time relay normally closed contact K2, and the time relay coil L1 and the time relay normally closed contact K2 are connected by magnetic coupling.
The time relay coil L1 is connected with a normally open contact K3 of the contactor through a line; the contactor coil L2, the switch power supply and the time relay normally closed contact K2 are connected in a line.
The closing condition of the time relay normally closed contact K2 is that the time relay coil L1 is not energized and the set time of the time relay is not reached. The closed condition of the normally open contact K3 of the contactor is the excitation of the contactor coil L2.
The monitoring unit 2 is provided with an ammeter a and a voltmeter V. The load unit 5 is a high power ripple resistor R.
The connection relation of the electrical elements of the device for detecting the voltage carried by the relay contact and switching on the carried current is as follows: one end of the tested contact K1 interface 4 is connected with one end of the ammeter A; the other end of the tested contact K1 interface 4 is respectively connected with one end of a time relay coil L1 and one end of a contactor normally open contact K3; the other end of the ammeter A is respectively connected with one end of a voltmeter V and one end of a voltage source 1; the other end of the voltmeter V and the other end of the voltage source 1 are both connected with the other end of the time relay coil L1; the other end of the time relay coil L1 is connected with a high-power corrugated resistor R in series and then is connected with one end of a normally open contact K3 of the contactor; one end of the time relay normally closed contact K2 is sequentially connected in series with the switching power supply and the contactor coil L2 and then connected with the other end of the time relay normally closed contact K2.
Through the electrical components and the connection relationship thereof, the detection principle of the device for detecting the relay contact bearing voltage and the relay contact connection bearing current is as follows:
1. when the tested contact interface K1 is in an off state, the two ends of the tested contact interface K bear the required bearing voltage, the amplitude of the bearing voltage is properly adjusted through the measurement result of the monitoring unit, and the voltmeter V carries out voltage inspection on the tested contact. Because the time relay normally closed contact K2 is in a closed state when the time relay coil L1 is not excited and the set time of the time relay is not reached; when the time relay normally closed contact K2 is closed, the contactor coil L2 is excited by the switching power supply, and the contactor normally open contact K3 is closed.
2. When the tested contact K1 is turned to the closed state from the open state, the tested contact K1 completes the on-current test, and the tested contact K1 enters the load current detection stage after entering the stable closed state.
3. The closing of the contact K1 to be tested causes the time relay coil L1 to be energized and starts the timing function, while a current is generated in the high power ripple resistor R. Because the impedance of the time relay coil L1 is far greater than the impedance of the high-power ripple resistor R, the current flowing through the high-power ripple resistor R can be considered as the switch-on load-carrying current of the contact to be tested approximately, and the amplitude of the switch-on load-carrying current is obtained by the ammeter A.
4. When the time relay coil L1 reaches the timing, namely the tested contact K1 reaches the specified on-load time, the normally closed contact K2 of the normally closed time relay is disconnected, the contactor coil L2 loses excitation, and the corresponding normally open contact K3 of the contactor is also disconnected, so that the on-load current of the tested contact is cut off.
5. After the normally open contact K3 of the contactor is opened, the current shown by the ammeter A is only the current flowing through the coil L1 of the time relay, and the current is approximately zero and is far lower than the amplitude of the on-load current and completely within the range of the opening capacity of the contact K1 to be tested, so that the contact K1 to be tested can be manually opened at the moment.
The device for detecting the voltage carried by the relay contact and switching on the carried current is provided with a voltage source 1, a monitoring unit 2, a time control cut-off unit 3, a tested contact K1 interface 4 and a load unit 5. The invention has the advantages that 1, the number of detection loops required can be reduced, namely, the same detection loop can finish the detection of the bearing voltage and the bearing current and simultaneously can reduce the probability of manually connecting the detection loops in a wrong way; 2. the number of times of wire replacement can be reduced, and the contact to be tested can be tested only by accessing the K1 interface 4 of the contact to be tested once; 3. the time for switching on the load current can be accurately timed, so that errors caused by manual timing are avoided; 4. the switch-on bearing current of the tested contact K1 interface 4 can be automatically cut off; 5. a user can manually disconnect the tested contact K1 according to the current shown by the monitoring unit, and the normally open contact K3 of the contactor is ensured to be disconnected before the tested contact K1, so that the risk that the tested contact K1 bears high-energy arc discharge due to manual operation sequence reversal is avoided; 6. and truly simulating a large power load.
Example 2.
A device for detecting voltage bearing of relay contact and switching on bearing current, other characteristics are the same as embodiment 1, except that: the timing range of the time relay coil L1 is 0.1 second-99 hours, the time resolution is greater than or equal to 100 milliseconds, the minimum breaking capacity of the contactor assembly is 30 amperes, the measuring range of the voltmeter V is 600 volts, the measuring range of the ammeter A is 100 amperes, the resistance value of the high-power ripple resistor R is 8.33 ohms, and the voltage source 1 is an AC/DC voltage source 1, and the capacity is greater than or equal to 7500 volt-ampere/watt.
The invention selects an AC or DC voltage source 1 according to the characteristics of the contact to be tested. Based on engineering experience, the carrying voltage of the tested contact is generally 250V, the limit switch-on carrying current is 30A, and the capacity of the voltage source 1 is at least 7500 volt-ampere/watt. The voltage source 1 is realized by a large-capacity voltage regulator, and the direct current voltage source 1 is realized by a large-capacity direct current power supply module.
The tested contact consists of a safe banana socket, a testing wire and an alligator clip. One section of the test wire is inserted into the banana socket, the other end of the test wire is inserted into the crocodile clip, and the test wire is reliably connected with the tested contact through the crocodile clip. And the safe banana socket is arranged on the panel, and the alligator clip can be replaced by a contact pin or an inserting sheet.
The excitation voltage of the time relay coil L1 of the present invention is matched to the AC/DC voltage source 1.
The device for detecting the voltage carried by the relay contact and switching on the carried current is provided with a voltage source 1, a monitoring unit 2, a time control cut-off unit 3, a tested contact K1 interface 4 and a load unit 5. The invention has the advantages that 1, the number of detection loops required can be reduced, namely, the same detection loop can finish the detection of the bearing voltage and the bearing current and simultaneously can reduce the probability of manually connecting the detection loops in a wrong way; 2. the number of times of wire replacement can be reduced, and the contact to be tested can be tested only by accessing the K1 interface 4 of the contact to be tested once; 3. the time for switching on the load current can be accurately timed, so that errors caused by manual timing are avoided; 4. the switch-on bearing current of the tested contact K1 interface 4 can be automatically cut off; 5. a user can manually disconnect the tested contact K1 according to the current shown by the monitoring unit, and the normally open contact K3 of the contactor is ensured to be disconnected before the tested contact K1, so that the risk that the tested contact K1 bears high-energy arc discharge due to manual operation sequence reversal is avoided; 6. and truly simulating a large power load.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.
Claims (5)
1. A device for detecting a voltage carried by a relay contact and for switching on the current carried by the relay contact, the device comprising: the device is provided with a voltage source, a monitoring unit, a time control current cutoff unit, a tested contact K1 interface and a load unit;
the voltage source provides the bearing voltage required by the contact to be tested and provides the required switch-on bearing current for the contact to be tested together with the load unit;
the tested contact K1 interface is connected with the tested contact;
the monitoring unit is used for monitoring the bearing voltage and switching on the bearing current;
the time control current-breaking unit is used for timing the on-load current and breaking the current before the tested contact is broken;
the load unit and the voltage source jointly provide the switch-on load current needed by the contact to be tested;
the time control current-cut unit is provided with a contactor assembly, a time relay assembly and a switching power supply, and the contactor assembly and the time relay assembly are respectively connected with the monitoring unit, a tested contact K1 interface, a voltage source, a load unit and the switching power supply;
the contactor assembly is provided with a contactor coil L2 and a contactor normally open contact K3, and the contactor normally open contact K3 and a contactor coil L2 are connected through magnetic coupling;
the time relay assembly is provided with a time relay coil L1 and a time relay normally closed contact K2, and the time relay coil L1 and the time relay normally closed contact K2 are connected through magnetic coupling;
the time relay coil L1 is connected with a normally open contact K3 of the contactor through a line;
the contactor coil L2, the switching power supply and the time relay normally closed contact K2 are connected through lines;
the closing condition of the time relay normally closed contact K2 is that the time relay coil L1 is not excited and does not reach the set time of the time relay;
the closing condition of the normally open contact K3 of the contactor is the excitation of a contactor coil L2.
2. The apparatus for detecting voltage carrying across a relay contact, completing a carrying current according to claim 1 wherein: the monitoring unit is provided with an ammeter A and a voltmeter V.
3. The apparatus for detecting voltage carrying across a relay contact, completing a carrying current according to claim 2 wherein: the load unit is a high-power ripple resistor R.
4. A device for detecting voltage carrying relay contacts, making a carrying current, according to claim 3, wherein: one end of the tested contact K1 interface is connected with one end of the ammeter A;
the other end of the tested contact K1 interface is respectively connected with one end of a time relay coil L1 and one end of a contactor normally open contact K3;
the other end of the ammeter A is respectively connected with one end of the voltmeter V and one end of the voltage source;
the other end of the voltmeter V and the other end of the voltage source are both connected with the other end of the time relay coil L1;
the other end of the time relay coil L1 is connected with a high-power corrugated resistor R in series and then is connected with one end of a normally open contact K3 of the contactor;
one end of the time relay normally closed contact K2 is sequentially connected in series with the switching power supply and the contactor coil L2 and then connected with the other end of the time relay normally closed contact K2.
5. The apparatus for detecting voltage carrying across a relay contact, completing a carrying current according to claim 4 wherein: the timing range of the time relay coil L1 is 0.1 second-99 hours, and the time resolution is more than or equal to 100 milliseconds;
the minimum breaking capacity of the contactor assembly is 30 amperes;
the measuring range of the voltmeter V is 600V;
the measuring range of the ammeter A is 100 amperes;
the resistance value of the high-power corrugated resistor R is 8.33 ohms;
the voltage source is an AC/DC voltage source and has a capacity greater than or equal to 7500 volt-ampere/watt.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911217984.8A CN110988666B (en) | 2019-12-03 | 2019-12-03 | Device for detecting voltage bearing and current bearing of relay contact |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911217984.8A CN110988666B (en) | 2019-12-03 | 2019-12-03 | Device for detecting voltage bearing and current bearing of relay contact |
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| CN110988666A CN110988666A (en) | 2020-04-10 |
| CN110988666B true CN110988666B (en) | 2021-11-02 |
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Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0917304A (en) * | 1995-06-29 | 1997-01-17 | Nec Yamagata Ltd | Relay deterioration measuring method |
| DE19603310A1 (en) * | 1996-01-31 | 1997-08-07 | Siemens Ag | Method for determining the remaining service life of contacts in switchgear and associated arrangement |
| CN1616976A (en) * | 2004-09-20 | 2005-05-18 | 江西洪都航空工业集团有限责任公司 | Automatic detecting system for relay |
| JP2006316639A (en) * | 2005-05-10 | 2006-11-24 | Denso Corp | Main relay failure diagnosing method and electronic control device |
| JP2006316638A (en) * | 2005-05-10 | 2006-11-24 | Denso Corp | Main relay failure diagnosing method and electronic control device |
| CN104345267B (en) * | 2013-07-24 | 2017-05-10 | 西安宝力电子科技有限公司 | Aging and early failure detection method and detection apparatus of solid relay |
| JP6146332B2 (en) * | 2013-09-11 | 2017-06-14 | トヨタ自動車株式会社 | Relay sticking detection system |
| CN104237782B (en) * | 2014-09-22 | 2018-02-16 | 力帆实业(集团)股份有限公司 | Starter relay durable systems and test method with safeguard protection and fault cues |
| CN105425144A (en) * | 2015-11-11 | 2016-03-23 | 浙江中控自动化仪表有限公司 | Relay fault detection circuit and fault detection method thereof |
| CN207114722U (en) * | 2017-08-31 | 2018-03-16 | 鄂尔多斯市中北煤化工有限公司 | Checking of great current circuit and flame-proof switch testboard |
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