CN212277783U - Automatic protection device of low-voltage drawer cabinet - Google Patents
Automatic protection device of low-voltage drawer cabinet Download PDFInfo
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- CN212277783U CN212277783U CN202020471203.XU CN202020471203U CN212277783U CN 212277783 U CN212277783 U CN 212277783U CN 202020471203 U CN202020471203 U CN 202020471203U CN 212277783 U CN212277783 U CN 212277783U
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Abstract
The utility model discloses a low pressure drawer cabinet automatic safety device is applicable to the three-phase major loop of low pressure drawer cabinet motor, include: the control circuit is electrically connected with a main contact of a contactor in the main circuit, the current transformer is arranged on the main circuit and used for collecting three-phase current data, the motor protector is electrically connected with the current transformer, at least one first protection relay is electrically connected with the motor protector and the control circuit, a protection power supply is used for supplying power to the motor protector, and at least one second protection relay is electrically connected with the protection power supply and the control circuit; the control loop is provided with a coil of the contactor and is used for controlling the main contact of the contactor to be closed or opened according to the power-on condition of the coil; when the motor protector detects that current data is abnormal, a coil of the contactor is controlled to be powered off through a first protective relay; and/or when the second protective relay detects that the protective power supply loses power, the coil of the contactor is controlled to be powered off, and the power supply of the motor is cut off, so that the motor is protected.
Description
Technical Field
The utility model relates to a low voltage distribution field especially relates to a low pressure drawer cabinet automatic safety device.
Background
In oil and gas exploitation, a large number of pumps are needed for supplying power to a large number of fluid media on site, so that a low-voltage drawer loaded with a motor in a low-voltage power distribution system of an offshore platform occupies a large part. The offshore platform belongs to a high-temperature, high-tide and high-salinity environment, an on-site motor is influenced by medium change and the environment, the phenomena of overload, overcurrent, locked rotor, no load and unbalanced three phases easily occur, and the motor is extremely easy to burn down to cause fire accidents when the motor runs for a long time without the protection function. Therefore, in the petrochemical industry, the automatic stopping protection function of the motor under the abnormal condition is very important.
In a conventional design, a main loop consisting of a circuit breaker, a fuse and a contactor is used for realizing overcurrent and overload protection of a motor; the secondary circuit only has simple opening and closing circuits, and only can start and stop the motor. Due to the limitation of the specification of the drawer, more components can not be installed, and more protection functions of the motor can not be realized. In addition, because the current and voltage data cannot be displayed at any time, the data can be measured only by manually using a multimeter and a pincerlike ammeter, the labor cost is increased, and all the problems result in that personnel cannot find the abnormal condition of the equipment at the first time.
SUMMERY OF THE UTILITY MODEL
The to-be-solved technical problem of the utility model lies in that, to prior art's defect, a low pressure drawer cabinet automatic safety device is provided.
The utility model provides a technical scheme that its technical problem adopted is: constructing a low-voltage drawer cabinet automatic protection device, suitable for the three-phase main loop of the low-voltage drawer cabinet motor, comprising:
the control circuit is electrically connected with a main contact of a contactor in the main circuit, the current transformer is arranged on the main circuit and used for collecting three-phase current data, the motor protector is electrically connected with the current transformer, at least one first protection relay is electrically connected with the motor protector and the control circuit, a protection power supply is used for supplying power to the motor protector, and at least one second protection relay is electrically connected with the protection power supply and the control circuit;
the control loop is internally provided with a coil of the contactor and is used for controlling the main contact of the contactor to be closed or opened according to the power-on condition of the coil;
when the motor protector detects that the current data is abnormal, controlling the coil of the contactor to be powered off through the first protective relay; and/or the presence of a gas in the gas,
and when the second protective relay detects that the protective power supply loses power, the coil of the contactor is controlled to be powered off, and the power supply of the motor is cut off.
Preferably, in the automatic protection device for a low-voltage drawer cabinet of the present invention, the second protection relay includes a coil disposed between the protection power supplies and a normally open auxiliary contact disposed in the control circuit;
when the protection power supply is normal, a coil of the second protection relay is electrified, the normally open auxiliary contact is closed, a coil of the contactor in the control loop is electrified, and a main contact of the contactor is closed;
when the protection power supply loses power, the coil of the second protection relay loses power, the normally-open auxiliary contact keeps disconnected, the coil of the contactor in the control loop loses power, and the main contact of the contactor is disconnected.
Preferably, in the automatic protection device for low-voltage drawer cabinets of the present invention, the second protection relay includes at least two coils connected in parallel between the protection power sources, and normally open auxiliary contacts connected in series in the control circuit respectively.
Preferably, in the automatic protection device for a low-voltage drawer cabinet of the present invention, the protection power supply is a dc24V power supply.
Preferably, in the automatic protection device for a low-voltage drawer cabinet of the present invention, the motor protector is an M101-P motor control device.
Preferably, in the automatic protection device for a low-voltage drawer cabinet of the present invention, the first protection relay includes a coil electrically connected to the motor protector, and a normally closed auxiliary contact disposed in the control circuit;
when the motor protector detects that the current data is normal, controlling a coil of the first protective relay not to be electrified, keeping the normally closed auxiliary contact closed, electrifying a coil of the contactor in the control loop, and closing a main contact of the contactor;
when the motor protector detects that the current data is abnormal, the coil of the first protective relay is controlled to be electrified, the normally closed auxiliary contact is disconnected, the coil of the contactor in the control loop is not electrified, and the main contact of the contactor is disconnected.
Preferably, in the automatic protection device for low-voltage drawer cabinet of the present invention, the automatic protection device for low-voltage drawer cabinet further comprises a test circuit connected to the control circuit, wherein the test circuit is used for testing whether the contactor is normal.
Preferably, in the automatic protection device for a low-voltage drawer cabinet of the present invention, the test circuit includes a test power supply, a test switch and a coil of a test relay disposed between the test power supply, and a test auxiliary contact of the test relay which is normally closed with the control circuit and normally open with the test power supply;
the circuit breaker in the main loop is disconnected, when the test switch is opened, the coil of the test relay is electrified, the test auxiliary contact is closed to the test power supply, and if the coil of the contactor in the control loop is electrified and the main contact of the contactor is closed, the contactor is normal; and if the coil of the contactor in the control loop loses power and the main contact of the contactor is disconnected, the contactor is abnormal.
Preferably, in the automatic protection device for a low-voltage drawer cabinet of the present invention, a button for controlling the start and stop of the motor is disposed on the control circuit.
Preferably, in the automatic protection device for low-voltage drawer cabinet of the present invention, the automatic protection device for low-voltage drawer cabinet further comprises a motor running indicator and a motor stop indicator, which are electrically connected to the control circuit.
Through implementing the utility model discloses, following beneficial effect has:
through the current transformer, the current information of the motor can be monitored and collected in real time, the accuracy of motor protection is improved, and the collected current information is subjected to data processing in the motor protector, and when the current data are found to be abnormal, the power supply of the motor can be cut off through the first protection relay, so that the protection functions of overcurrent, unbalanced three phases, no load, light load, locked rotor, overload and open phase of the motor are realized, and the protection functions are diversified;
through installing the second protective relay additional, just allow the starter motor after motor protector's protection power gets electric, lose the electricity when protection power, when motor protector loses protect function, cut off the motor power supply immediately, avoided the motor to operate for a long time under the condition that does not have protect function, play duplicate protection's effect.
The automatic protection device for the low-voltage drawer cabinet has the characteristics of continuity, diversity, duality, sensitive protection, high reliability and high automation degree to motor protection, and is suitable for automatic protection of a low-voltage drawer motor.
Drawings
The invention will be further explained with reference to the drawings and examples, wherein:
fig. 1 is a schematic block diagram of the automatic protection device for a low-voltage drawer cabinet of the present invention;
fig. 2 is a circuit diagram of the automatic protection device for the low-voltage drawer cabinet of the present invention.
Detailed Description
In order to clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
The utility model discloses low pressure drawer cabinet automatic safety device, current data is gathered often on the one hand, can realize the continuous incessant multi-functional protection to the motor, and on the other hand installs protection relay additional at control circuit, and protection power supply just allows the starter motor after getting the electricity, when can realizing that protection power supply loses the electricity, automatic cutout main loop power, the motor is automatic shutdown immediately to send alarm information, make things convenient for personnel in time to discover and handle the trouble. Through the utility model discloses very big enhancement low pressure drawer cabinet oneself and detected, oneself protect function such as oneself cuts off, improved the essential safety of equipment, technically provide the guarantee for safety in production.
The automatic protection device for the low-voltage drawer cabinet is suitable for a three-phase main loop of a motor of the low-voltage drawer cabinet, and as shown in fig. 2, the three-phase main loop comprises a breaker QF and a contactor KM 1. One end of the breaker QF is connected with a 400V low-voltage distribution busbar, and the other end of the breaker QF is connected with a contactor KM 1. In some embodiments, the low-voltage drawer cabinet is a plastic shell type circuit breaker which has the functions of connection, isolation and overcurrent protection. Moreover, the ESD emergency shutdown signal is generally connected to the trip coil of the circuit breaker, and will not be described herein.
One end of the contactor KM1 is connected with a breaker QF, the other end of the contactor KM1 is directly connected with a motor, and the inside of the contactor KM1 is composed of a coil, three main contacts and an auxiliary contact. In a secondary loop, the on-off of the main contact is controlled by controlling the on-off of the coil of the contactor KM1, so that the start and stop of the motor are controlled, and the effect of controlling the high voltage by the low voltage is realized.
This low pressure drawer cabinet automatic safety device includes: the control circuit is electrically connected with a main contact of the contactor KM1 in the main circuit, a current transformer TA which is arranged on the main circuit and used for collecting three-phase current data, a motor protector which is electrically connected with the current transformer TA, at least one first protection relay K4 which is electrically connected with the motor protector and the control circuit, a protection power supply which supplies power to the motor protector, and at least one second protection relay K9 and K10 which are electrically connected with the protection power supply and the control circuit;
the control loop is provided with a coil of the contactor KM1 and is used for controlling the main contact of the contactor to be closed or opened according to the power-on condition of the coil; when the motor protector detects that current data are abnormal, the coil of the contactor KM1 is controlled to be powered off through a first protective relay K4; and/or when the second protection relay detects that the protection power supply is power-off, the coil of the control contactor KM1 is powered off, and the power supply of the motor is cut off.
In this embodiment, in the three-phase line of the main circuit, each line passes through a current transformer TA that monitors the current signal from time to time, and the current transformer TA is connected to the motor protector. The motor protector is an M101-P motor control device, collects three-phase current constantly, and can realize the protection functions of overcurrent, three-phase unbalance, no-load, light load, locked rotor, overload and open phase of the motor through internal data operation. When the motor protector detects that three-phase current data is abnormal, the contact on the first protection relay K4 is triggered to act, and a control loop is automatically cut off, so that the coil of the contactor KM1 is powered off, three main contacts of the contactor KM1 are disconnected, the motor is stopped, and the function of protecting the motor is achieved.
In the present embodiment, the first protective relay K4 includes a coil electrically connected to the motor protector, and a normally closed auxiliary contact provided in the control circuit. When the motor protector detects that current data are normal, controlling a coil of a first protective relay K4 not to be electrified, keeping a normally closed auxiliary contact closed, controlling a coil of a contactor KM1 in a loop to be electrified, and closing a main contact of a contactor KM 1; when the motor protector detects that current data is abnormal, a coil of the first protection relay K4 is controlled to be powered on, the normally closed auxiliary contact is disconnected, a coil of the contactor KM1 in the control loop is powered off, and a main contact of the contactor KM1 is disconnected.
In this embodiment, a protective power supply is provided for the motor protector, in some embodiments, a 24V DC power supply, such as DC24V shown in fig. 2. The second protective relay comprises a coil arranged between the protective power supplies and a normally open auxiliary contact arranged in the control loop. When the protection power supply is normal, the coil of the second protection relay is electrified, the normally open auxiliary contact is closed, the coil of the contactor KM1 in the control loop is electrified, and the main contact of the contactor KM1 is closed; when the protection power supply loses power, the coil of the second protection relay loses power, the normally-open auxiliary contact is kept disconnected, the coil of the contactor KM1 in the control loop loses power, and the main contact of the contactor KM1 is disconnected.
In some embodiments, at least two second protective relays are included, the coils of the second protective relays are connected between the protective power supplies in parallel, and the normally open auxiliary contacts of the second protective relays are connected in series in the control loop respectively. In the present embodiment, as shown in fig. 2, second protective relays K9 and K10 are included, which are distributed at the upper and lower ends of the control circuit.
In some embodiments, the automatic low-voltage drawer cabinet protection device further comprises a central control remote start-stop unit PCS connected to the protection power supply and the motor protector for remotely starting the motor protector. In this embodiment, after the motor protector is started, switches in the control circuit related to the motor protector are all triggered and in a closed state, which is not described herein again.
In this embodiment, the automatic protection device for the low-voltage drawer cabinet further includes a test loop connected to the control loop, where the test loop is used to test whether the contactor KM1 is normal, and whether the start/stop of the motor is normal and whether the protection loop operates normally is simulated by testing whether the contactor KM1 is engaged.
The testing loop comprises testing power supplies, coils of a testing switch Test and a testing relay K2 which are arranged between the testing power supplies, and testing auxiliary contacts of a testing relay K2 which is normally closed with the control loop and is normally open with the testing power supplies. When a breaker QF in the main loop is disconnected and a Test switch Test is started, a coil of a Test relay K2 is electrified, a Test auxiliary contact is closed to a Test power supply, namely a control circuit is connected to the Test power supply, and if a coil of a contactor KM1 in the control loop is electrified and a main contact of a contactor KM1 is closed, a contactor KM1 is normal; if the coil of the contactor KM1 in the control loop loses power and the main contact of the contactor KM1 is opened, the contactor KM1 is abnormal. In this embodiment, the test power supply is a 110V AC power supply, such as AC110V shown in FIG. 2.
In this embodiment, the control loop includes: the testing device is characterized in that a fuse FU1, a control transformer TC, a testing auxiliary contact of a normally closed testing relay K2, a normally open auxiliary contact of a second protection relay K9, a normally closed auxiliary contact of a first protection relay K4, a coil of a contactor KM1, a normally open auxiliary contact of a second protection relay K10 and a testing auxiliary contact of a normally closed testing relay K2 which form a loop are sequentially connected. Wherein the fuse FU1 is connected between the main power supply and the control power supply.
In this embodiment, a start button SB1 for controlling the motor to start and a stop button SB2 for controlling the motor to stop are also provided on the control circuit.
In some embodiments, the automatic protection device for the low-voltage drawer cabinet further comprises a motor running indicator light and a motor stop indicator light which are electrically connected with the control loop.
In some embodiments, the current information acquired by the current transformer TA may be further processed, such as installing a current monitoring and displaying device, or performing calculation processing on the current information by using big data, checking a current curve of the motor, and predicting a potential fault of the motor; meanwhile, the alarm information can be further upgraded and processed, specific alarm is displayed, and people can conveniently and rapidly lock reasons.
In some embodiments, the automatic protection device for the low-voltage drawer cabinet can be disposed in a Manual cabinet, a Pms cabinet or an Auto cabinet, and different drawer cabinets can be selected to protect the motor according to actual conditions, and the Manual contact, the Pms contact or the Auto contact of the different drawer cabinets can be in a closed state to communicate with the control loop.
The utility model discloses a theory of operation is: the motor protector passes through current transformer TA and gathers three-phase current data often, when motor protector detects three-phase current data unusual, triggers first protective relay K4's coil and gets electric, and the disconnection of the normally closed auxiliary contact in the control circuit, automatic cutout control circuit to make contactor KM1 coil outage, make contactor KM 1's three main contact disconnection, the motor is shut down, reaches the function of protection motor. A 24VDC second protection relay is additionally arranged on a power supply of the motor protector, when the power supply of the motor protector is powered off, on one hand, a coil of the second protection relay is triggered to be powered off, a normally open auxiliary contact in a control loop is kept disconnected, so that the coil of the contactor KM1 is powered off, three main contacts of the contactor KM1 are disconnected, and the motor is stopped; on the other hand, the operation/stop indicator lamp of the drawer panel can be extinguished, and the stop signal can be fed back to the central control room rapidly, so that the response speed of field personnel in abnormal conditions is improved, the reason can be searched for in the first time, the motor is prevented from operating under the condition of loss of the protection function, and the motor burnout accident is avoided.
Through implementing the utility model discloses, following beneficial effect has:
through the current transformer, the current information of the motor can be monitored and collected in real time, the accuracy of motor protection is improved, and the collected current information is subjected to data processing in the motor protector, and when the current data are found to be abnormal, the power supply of the motor can be cut off through the first protection relay, so that the protection functions of overcurrent, unbalanced three phases, no load, light load, locked rotor, overload and open phase of the motor are realized, and the protection functions are diversified;
through installing the second protective relay additional, just allow the starter motor after motor protector's protection power gets electric, lose the electricity when protection power, when motor protector loses protect function, cut off the motor power supply immediately, avoided the motor to operate for a long time under the condition that does not have protect function, play duplicate protection's effect.
The automatic protection device for the low-voltage drawer cabinet has the characteristics of continuity, diversity, duality, sensitive protection, high reliability and high automation degree to motor protection, and is suitable for automatic protection of a low-voltage drawer motor.
It is to be understood that the foregoing examples merely represent preferred embodiments of the present invention, and that the description thereof is more specific and detailed, but not intended to limit the scope of the invention; it should be noted that, for those skilled in the art, the above technical features can be freely combined, and several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention; therefore, all changes and modifications that come within the meaning and range of equivalency of the claims are to be embraced within their scope.
Claims (10)
1. The utility model provides a low pressure drawer cabinet automatic safety device, is applicable to the three-phase major loop of low pressure drawer cabinet motor, its characterized in that includes:
the control circuit is electrically connected with a main contact of a contactor in the main circuit, the current transformer is arranged on the main circuit and used for collecting three-phase current data, the motor protector is electrically connected with the current transformer, at least one first protection relay is electrically connected with the motor protector and the control circuit, a protection power supply is used for supplying power to the motor protector, and at least one second protection relay is electrically connected with the protection power supply and the control circuit;
the control loop is internally provided with a coil of the contactor and is used for controlling the main contact of the contactor to be closed or opened according to the power-on condition of the coil;
when the motor protector detects that the current data is abnormal, controlling the coil of the contactor to be powered off through the first protective relay; and/or the presence of a gas in the gas,
and when the second protective relay detects that the protective power supply loses power, the coil of the contactor is controlled to be powered off, and the power supply of the motor is cut off.
2. The automatic protection device for the low-voltage drawer cabinet according to claim 1, wherein the second protection relay comprises a coil arranged between the protection power supply and a normally open auxiliary contact arranged in the control loop;
when the protection power supply is normal, a coil of the second protection relay is electrified, the normally open auxiliary contact is closed, a coil of the contactor in the control loop is electrified, and a main contact of the contactor is closed;
when the protection power supply loses power, the coil of the second protection relay loses power, the normally-open auxiliary contact keeps disconnected, the coil of the contactor in the control loop loses power, and the main contact of the contactor is disconnected.
3. The automatic protection device for low-voltage drawer cabinet according to claim 2, comprising at least two second protection relays, wherein the coils of the second protection relays are connected in parallel between the protection power sources, and the normally open auxiliary contacts of the second protection relays are respectively connected in series in the control loop.
4. The automatic protection device for low-voltage drawer cabinet according to claim 1, wherein the protection power supply is a direct current 24V power supply.
5. The automatic low-voltage drawer cabinet protector as claimed in claim 1, wherein the motor protector is an M101-P motor control device.
6. The automatic low-voltage drawer cabinet protection device according to claim 1, wherein the first protection relay comprises a coil electrically connected with the motor protector and a normally closed auxiliary contact arranged in the control loop;
when the motor protector detects that the current data is normal, controlling a coil of the first protective relay not to be electrified, keeping the normally closed auxiliary contact closed, electrifying a coil of the contactor in the control loop, and closing a main contact of the contactor;
when the motor protector detects that the current data is abnormal, the coil of the first protective relay is controlled to be electrified, the normally closed auxiliary contact is disconnected, the coil of the contactor in the control loop is not electrified, and the main contact of the contactor is disconnected.
7. The automatic protection device for low-voltage drawer according to claim 1, further comprising a test circuit connected to the control circuit, wherein the test circuit is used to test whether the contactor is normal.
8. The automatic protection device for the low-voltage drawer cabinet according to claim 7, wherein the test loop comprises a test power supply, a test switch and a coil of a test relay which are arranged between the test power supply, and a test auxiliary contact of the test relay which is normally closed with the control loop and is normally open with the test power supply;
the circuit breaker in the main loop is disconnected, when the test switch is opened, the coil of the test relay is electrified, the test auxiliary contact is closed to the test power supply, and if the coil of the contactor in the control loop is electrified and the main contact of the contactor is closed, the contactor is normal; and if the coil of the contactor in the control loop loses power and the main contact of the contactor is disconnected, the contactor is abnormal.
9. The automatic protection device for low-voltage drawer cabinet as claimed in claim 1, wherein the control circuit is provided with a button for controlling the motor to start and stop.
10. The automatic low-voltage drawer cabinet protection device according to claim 1, further comprising a motor running indicator and a motor stop indicator electrically connected to the control circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020471203.XU CN212277783U (en) | 2020-04-02 | 2020-04-02 | Automatic protection device of low-voltage drawer cabinet |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020471203.XU CN212277783U (en) | 2020-04-02 | 2020-04-02 | Automatic protection device of low-voltage drawer cabinet |
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| CN212277783U true CN212277783U (en) | 2021-01-01 |
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| CN202020471203.XU Active CN212277783U (en) | 2020-04-02 | 2020-04-02 | Automatic protection device of low-voltage drawer cabinet |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113945148A (en) * | 2021-10-15 | 2022-01-18 | 衡阳泰豪通信车辆有限公司 | In-place detection circuit and method for vehicle-mounted lifting mechanism |
-
2020
- 2020-04-02 CN CN202020471203.XU patent/CN212277783U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113945148A (en) * | 2021-10-15 | 2022-01-18 | 衡阳泰豪通信车辆有限公司 | In-place detection circuit and method for vehicle-mounted lifting mechanism |
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