CN209250221U - Low load current automatic detection's earth-leakage protector - Google Patents
Low load current automatic detection's earth-leakage protector Download PDFInfo
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- CN209250221U CN209250221U CN201920053361.0U CN201920053361U CN209250221U CN 209250221 U CN209250221 U CN 209250221U CN 201920053361 U CN201920053361 U CN 201920053361U CN 209250221 U CN209250221 U CN 209250221U
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Abstract
The utility model discloses a low load current automated inspection's earth-leakage protector, establish zero sequence current transformer TA1 on phase line and zero line including the cover, zero sequence current transformer TA1 load side is connected with phase line current transformer TA2, main switch KM1 in order, zero sequence current transformer TA1 phase line is connected with the current-limiting resistor subassembly, be connected with the automated inspection switch between current-limiting resistor subassembly and the zero sequence current transformer TA1 load side zero line, zero sequence current transformer TA1 secondary coil output is connected with zero sequence current signal processor and controller in order, the controller embeds or is connected with the time-recorder module that is used for regularly automated inspection timing and main switch KM1 not tripping operation timing, the controller is connected with the phase line current signal processor who is connected with phase line current transformer TA2, is used for driving the automated inspection switch driver of automated inspection switch break-make-break-and-break, And the switching on and switching off device is used for driving the main switch KM1 to be switched on and switched off.
Description
[technical field]
The utility model relates to a kind of earth leakage protective devices that low-load electric current detects automatically.
[background technique]
As electricity consumption, electrical disaster caused by improper or line electrical leakage happens occasionally in daily production and life, causes
Immeasurable casualties and property loss.It is to avoid physical electrical shock fire protection injures and deaths that earth leakage protective device is installed in low-voltage distribution system
The effective measures of electrical fire caused by accident and electric leakage, electrical equipment damage accident.The electrical installation of most countries is advised
Range request regularly detects the performance of protector, China's electric power safety regulation, and earth leakage protective device will carry out once at least every month
Whether detection, verifying creepage protection function are normal.But it has more than 90% user there is no periodic detection as required, wind
Danger can not be underestimated.
[utility model content]
The utility model overcomes the deficiency of above-mentioned technology, provides a kind of earth leakage protective that low-load electric current detects automatically
Device.
To achieve the above object, the utility model uses following technical proposal:
A kind of earth leakage protective device that low-load electric current detects automatically includes the zero-sequence current being set in phase line and zero curve
Mutual inductor TA1, the zero sequence current mutual inductor TA1 load-side is connected with the main switch KM1 of control phase line and zero curve on-off, described
The phase line electricity for detecting load current is connected in phase line between zero sequence current mutual inductor TA1 load-side and main switch KM1
Current transformer TA2, the zero sequence current mutual inductor TA1 source side phase line are connected with current-limiting resistance component 1, the current-limiting resistance group
Part 1 is connected with automatic detection switch 2, and automatic 2 other end of detection switch and zero sequence current mutual inductor TA1 load-side zero curve connect
It connecing, the zero sequence current mutual inductor TA1 secondary coil output end has been sequentially connected with zero sequence current signal processor 4 and controller 5,
The controller 5 is built-in with or is connected with not to trip the timer mould of timing for the automatic detection timing of timing and main switch KM1
Block 12, the controller 5 are connected with the phase line current signal processor 6 connecting with phase line current mutual inductor TA2, for driving certainly
Automatic detection switch driver 7, the closing-opening device 8 for driving main switch KM1 on-off of dynamic 2 on-off of detection switch.
The controller 5 is connected with load voltage detector 9 for detecting main switch KM1 on-off, for working as main switch
When KM1 does not jump disconnected and load voltage detector 9 detects that loading the combined aural and visual alarm 11 that sound-light alarm is carried out when having voltage reports
It is alert.
The current-limiting resistance component 1 is connected with the ground line current switch 3 being powered for disconnecting higher-level leakage protector, institute
It states 3 other end of ground line current switch to connect with ground wire, the controller 5 is connected with for driving 3 on-off of ground line current switch
Ground line current switch driver 10.
The controller 5 is connected with does not jump for setting the automatic detection time of 12 timing of Timer module and main switch KM1
Lock time, the automatic numerical value setter 13 for detecting minimum load current value of setting timing.
The main switch KM1 source side phase line connects the power circuit 14 that oriented controller 5 is powered.
It is triggered when being equipped with detection manually between the current-limiting resistance component 1 and zero sequence current mutual inductor TA1 load-side zero curve
Zero sequence current mutual inductor TA1 is set to generate the manual detection switch SB of zero-sequence current.
The current-limiting resistance component 1 includes resistance R1 and resistance R2, and the one end resistance R1 and zero sequence current mutual inductor TA1 are electric
The connection of source phase line, the resistance R1 other end are connect with the one end resistance R2, ground line current switch 3 respectively, resistance R2 other end difference
It is connect with automatic detection switch 2, manual detection switch SB.
The current-limiting resistance component 1 includes resistance R1 and resistance R2, and the one end resistance R1 and the one end resistance R2 are respectively with zero
Sequence current transformer TA1 source side phase line connection, the resistance R1 other end respectively with automatic detection switch 2, manual detection switch SB
Connection, the resistance R2 other end are connect with ground line current switch 3.
The automatic detection switch 2 is the mechanical switch KM2 driven by automatic detection switch driver 7, the ground wire electricity
Flowing switch 3 is the mechanical switch KM3 driven by ground line current switch driver 10.
The automatic detection switch 2 is thyristor Q1, and thyristor Q1 positive terminal is connect with resistance R1, thyristor Q1 negative pole end
Connect respectively with zero sequence current mutual inductor TA1 load-side zero curve, the one end capacitor C1, the capacitor C1 other end respectively with thyristor Q1
Extremely, detection switch driver 7 connects automatically, and the ground line current switch 3 is thyristor Q2, thyristor Q2 positive terminal and resistance
R2 connection, thyristor Q2 negative pole end are connect with ground wire, the one end capacitor C2 respectively, the capacitor C2 other end respectively with thyristor Q2 gate pole
End, ground line current switch driver 10 connect.
The beneficial effects of the utility model are:
1, the utility model can load very little or when being zero after in the time of setting, the earth leakage protective detected automatically
Whether device closing-opening device is normal, can not only realize band breaker tripping and closing self-test, high current when can also prevent self-test frequent breaker tripping and closing
Burn out main switch contact.
2, the utility model structure is simple, long service life, easy to manufacture, at low cost.
[Detailed description of the invention]
Fig. 1 is one structural schematic diagram of the utility model embodiment；
Fig. 2 is two structural schematic diagram of the utility model embodiment；
Fig. 3 is three structural schematic diagram of the utility model embodiment.
Power supply line symbol description in figure: L is phase line, and N is zero curve, and PE is ground wire.
[specific embodiment]
The technical solution of the utility model embodiment is explained below with reference to the attached drawing of the utility model embodiment and
Illustrate, but following embodiments are only the preferred embodiment of the utility model, and not all.Based on the implementation example in the implementation mode,
Those skilled in the art's obtained other embodiments without making creative work, belong to the guarantor of the utility model
Protect range.
Embodiment one:
As shown in Figure 1, a kind of earth leakage protective device that low-load electric current detects automatically, includes to be set in phase line and zero curve
Zero sequence current mutual inductor TA1, the zero sequence current mutual inductor TA1 load-side is connected with control phase line and the master of zero curve on-off opens
Close KM1, it is characterised in that: be connected with and be used in the phase line between the zero sequence current mutual inductor TA1 load-side and main switch KM1
The phase line current mutual inductor TA2 of load current is detected, the zero sequence current mutual inductor TA1 source side phase line is connected with current-limiting resistance
Component 1, the current-limiting resistance component 1 are connected with the automatic detection switch 2 detected automatically for low-load electric current, the automatic inspection
It surveys 2 other end of switch to connect with zero sequence current mutual inductor TA1 load-side zero curve, the zero sequence current mutual inductor TA1 secondary coil
Output end has been sequentially connected with zero sequence current signal processor 4 and controller 5, and the controller 5 is built-in with or is connected with for fixed
Shi Zidong detection timing and main switch KM1 do not trip the Timer module 12 of timing, and the controller 5 is connected with and phase line current
The phase line current signal processor 6 of mutual inductor TA2 connection, for driving the automatic detection switch of automatic 2 on-off of detection switch to drive
Dynamic device 7, the closing-opening device 8 for driving main switch KM1 on-off.
Wherein, the controller 5 is connected with load voltage detector 9 for detecting main switch KM1 on-off, for as master
When switch KM1 does not jump disconnected and load voltage detector 9 detects the combined aural and visual alarm for loading and carrying out sound-light alarm when having voltage
11。
The current-limiting resistance component 1 is connected with the ground line current switch 3 being powered for disconnecting higher-level leakage protector, institute
It states 3 other end of ground line current switch to connect with ground wire, the controller 5 is connected with for driving 3 on-off of ground line current switch
Ground line current switch driver 10.
It is triggered when being equipped with detection manually between the current-limiting resistance component 1 and zero sequence current mutual inductor TA1 load-side zero curve
Zero sequence current mutual inductor TA1 is set to generate the manual detection switch SB of zero-sequence current.
The current-limiting resistance component 1 includes resistance R1 and resistance R2, and the one end resistance R1 and zero sequence current mutual inductor TA1 are electric
The connection of source phase line, the resistance R1 other end are connect with the one end resistance R2, ground line current switch 3 respectively, resistance R2 other end difference
It is connect with automatic detection switch 2, manual detection switch SB.
The automatic detection switch 2 is the mechanical switch KM2 driven by automatic detection switch driver 7, the ground wire electricity
Flowing switch 3 is the mechanical switch KM3 driven by ground line current switch driver 10.
Operation manual handle closes main switch KM1 every time, and user starts electricity consumption, while timer 12 starts the automatic inspection of timing
The timing of survey, after timing to setting time, the load current of phase line current mutual inductor TA2 detection, and pass through phase line current signal
After the processing of processor 6, the load current value exported to controller 5 is more than or equal to load current set values, and setting value can be 0, then
Continue to monitor, when load current drops below setting value, controller 5 controls automatic 7 driving machine of detection switch driver
Tool switch KM2 closure, zero sequence current mutual inductor TA1 exports remaining zero-sequence current and handles through zero sequence current signal processor 4 at this time
Afterwards, trigger signal is exported to controller 5, controller 5, which exports trip signal, keeps the control of closing-opening device 8 contact main switch KM1 disconnected
It opens, load voltage detector 9 exports no-voltage signal into controller 5 at this time, that is, illustrates that earth leakage protective device tripping is normal, then
Controller 5 controls automatic detection switch driver 7 and mechanical switch KM2 is driven to disconnect, and then exporting switching signal fills on/off switch
8 control main switch KM1 contact closures are set, the output of load voltage detector 9 at this time has voltage signal into controller 5, timer
12 timing detection timing resets and restarts timing, and user can continue electricity consumption, realize the timing of earth leakage protective device small
Automatic detection when load current or no-load current.
If breaking down, it is still "on" position that main switch KM1 contact, which does not turn off, and the output of load voltage detector 9 has voltage
Signal illustrates that earth leakage protective device work is abnormal, controller 5 controls combined aural and visual alarm 11 and issues acousto-optic at this time into controller 5
Alarm signal, timer 12 start main switch KM1 and do not trip timing；After timing to setting time, main switch KM1 does not trip still,
Load voltage detector 9 has still been detected as voltage signal output, then 5 control switch driver 7 of controller drives mechanical switch KM2
It disconnects, and controls ground line current switch driver 10 and drive mechanical switch KM3 closure, pass the current through current-limiting resistance R1 from phase line
L flows to ground wire PE, so that higher-level leakage protector is tripped, so that it is guaranteed that Electrical Safety.
User can also realize detection manually by manual detection switch SB, press manual detection switch SB, and electric shock is connected, zero
The remaining zero-sequence current of sequence current transformer TA1 output is exported to controller 5 and is touched after the processing of zero sequence current signal processor 4
It signals, controller 5, which exports trip signal, makes closing-opening device 8 control the disconnection of the contact main switch KM1, the timing inspection of timer 12
Timing is surveyed to reset, thus realize the manual detection to earth leakage protective device, release button after the completion of detecting manually, manual detection switch
The contact SB disconnects, and operation manual handle closes main switch KM1, and timer 12 starts timing detection timing, and user can continue electricity consumption.
Wherein, the controller 5 is connected with does not jump for setting the automatic detection time of 12 timing of timer and main switch KM1
It lock time, the automatic numerical value setter 13 for detecting minimum load current value of setting timing, is set separately by numerical value setter 13
Determine the automatic detection time of timing of timer 12, main switch KM1 not the trip time or not may be configured as 0 and timing from
Dynamic detection minimum load current value.
The main switch KM1 source side phase line connects the power circuit 14 that oriented controller 5 is powered.
Embodiment two:
As shown in Fig. 2, the current-limiting resistance component 1 includes resistance R1 and resistance R2, the one end resistance R1 and resistance R2 mono-
End connect with zero sequence current mutual inductor TA1 source side phase line respectively, the resistance R1 other end respectively with automatic detection switch 2, manual
Detection switch SB connection, the resistance R2 other end are connect with ground line current switch 3.
The automatic detection switch 2 is the mechanical switch KM2 driven by automatic detection switch driver 7, the ground wire electricity
Flowing switch 3 is the mechanical switch KM3 driven by ground line current switch driver 10.
Embodiment two is that the connection type of resistance R1 and R2 in current-limiting resistance component 1 are different from the difference of embodiment one,
Resistance R1, which breaks down, in embodiment two nor affects on the function of realization higher-level leakage protector tripping, further ensures that electricity consumption is pacified
Entirely.
Embodiment three:
As shown in figure 3, the current-limiting resistance component 1 includes resistance R1 and resistance R2, the one end resistance R1 and resistance R2 mono-
End connect with zero sequence current mutual inductor TA1 source side phase line respectively, the resistance R1 other end respectively with automatic detection switch 2, manual
Detection switch SB connection, the resistance R2 other end are connect with ground line current switch 3.
The automatic detection switch 2 is thyristor Q1, and thyristor Q1 positive terminal is connect with resistance R1, thyristor Q1 negative pole end
Connect respectively with zero sequence current mutual inductor TA1 load-side zero curve, the one end capacitor C1, the capacitor C1 other end respectively with thyristor Q1
Extremely, detection switch driver 7 connects automatically, and the ground line current switch 3 is thyristor Q2, thyristor Q2 positive terminal and resistance
R2 connection, thyristor Q2 negative pole end are connect with ground wire, the one end capacitor C2 respectively, the capacitor C2 other end respectively with thyristor Q2 gate pole
End, ground line current switch driver 10 connect.
The difference of embodiment three and embodiment two is to substitute respectively using the triggering and conducting of thyristor Q1 and thyristor Q2
Relay mechanical switch KM2 and the conducting of relay mechanical switch KM3 contact closure, can prevent the frequent on-off of mechanical contact from influencing the longevity
Life.
The utility model can be applied not only to installing type earth leakage protective device, can also be applied to rail conduction earth leakage protective
Device, with earth leakage protective power outlet or insert row, with earth leakage protective mobile power socket or insert row, with earth leakage protective power supply
Plug, the equipment with earth leakage protective plug and socket of power source or insert row converter etc. in relation to list, three phase mains, do not arrange one by one herein
It lifts, it is all to belong to scope of protection of the utility model using the utility model in the earth leakage protective in relation to power supply.
Claims (10)
- It include that the zero-sequence current that is set in phase line and zero curve is mutual 1. a kind of earth leakage protective device that low-load electric current detects automatically Sensor TA1, the zero sequence current mutual inductor TA1 load-side are connected with the main switch KM1 of control phase line and zero curve on-off, feature It is: is connected in the phase line between the zero sequence current mutual inductor TA1 load-side and main switch KM1 for detecting load current Phase line current mutual inductor TA2, the zero sequence current mutual inductor TA1 source side phase line is connected with current-limiting resistance component (1), described Current-limiting resistance component (1) is connected with automatic detection switch (2), automatic detection switch (2) other end and zero sequence current mutual inductance The connection of device TA1 load-side zero curve, the zero sequence current mutual inductor TA1 secondary coil output end have been sequentially connected with zero sequence current signal Processor (4) and controller (5), the controller (5) are built-in with or are connected with for the automatic detection timing of timing and main switch KM1 does not trip the Timer module (12) of timing, and the controller (5) is connected with the phase connecting with phase line current mutual inductor TA2 Line current signal processor (6), the automatic detection switch driver (7) for driving automatic detection switch (2) on-off, for driving The closing-opening device (8) of dynamic main switch KM1 on-off.
- 2. a kind of earth leakage protective device that low-load electric current detects automatically according to claim 1, it is characterised in that: the control Device (5) processed is connected with load voltage detector (9) for detecting main switch KM1 on-off, for when main switch KM1 does not jump disconnected And load voltage detector (9) detects combined aural and visual alarm (11) alarm that sound-light alarm is carried out when having voltage in load.
- 3. a kind of earth leakage protective device that low-load electric current detects automatically according to claim 1, it is characterised in that: the limit Leakage resistance component (1) is connected with the ground line current switch (3) being powered for disconnecting higher-level leakage protector, the ground line current Switch (3) other end is connect with ground wire, and the controller (5) is connected with the ground wire for driving ground line current switch (3) on-off Current switch driver (10).
- 4. a kind of earth leakage protective device that low-load electric current detects automatically according to claim 3, it is characterised in that: the control Device (5) processed is connected with for setting the automatic detection time of Timer module (12) timing and main switch KM1 not trip time, setting The numerical value setter (13) of the automatic detection minimum load current value of timing.
- 5. a kind of earth leakage protective device that low-load electric current detects automatically according to claim 1, it is characterised in that: the master Switch KM1 source side phase line connects the power circuit (14) of oriented controller (5) power supply.
- 6. a kind of earth leakage protective device that low-load electric current detects automatically according to claim 1, it is characterised in that: the limit Triggering keeps zero-sequence current mutual when being equipped with detection manually between leakage resistance component (1) and zero sequence current mutual inductor TA1 load-side zero curve The manual detection switch SB of sensor TA1 generation zero-sequence current.
- 7. a kind of earth leakage protective device that low-load electric current detects automatically according to claim 6, it is characterised in that: the limit Leakage resistance component (1) includes resistance R1 and resistance R2, and the one end resistance R1 and zero sequence current mutual inductor TA1 source side phase line connect It connects, the resistance R1 other end is connect with the one end resistance R2, ground line current switch (3) respectively, and the resistance R2 other end is examined with automatic respectively Survey switch (2), manual detection switch SB connection.
- 8. a kind of earth leakage protective device that low-load electric current detects automatically according to claim 6, it is characterised in that: the limit Leakage resistance component (1) includes resistance R1 and resistance R2, the one end resistance R1 and the one end resistance R2 respectively with zero sequence current mutual inductor The connection of TA1 source side phase line, the resistance R1 other end are connect with automatic detection switch (2), manual detection switch SB respectively, resistance R2 The other end is connect with ground line current switch (3).
- 9. a kind of earth leakage protective device that low-load electric current detects automatically according to claim 7 or 8, it is characterised in that: institute Stating automatic detection switch (2) is the mechanical switch KM2 driven by automatic detection switch driver (7), the ground line current switch (3) the mechanical switch KM3 to be driven by ground line current switch driver (10).
- 10. a kind of earth leakage protective device that low-load electric current detects automatically according to claim 8, it is characterised in that: described Automatic detection switch (2) is thyristor Q1, and thyristor Q1 positive terminal is connect with resistance R1, thyristor Q1 negative pole end respectively with zero sequence Current transformer TA1 load-side zero curve, the connection of the one end capacitor C1, the capacitor C1 other end respectively with thyristor Q1 gate terminal, automatic Detection switch driver (7) connection, the ground line current switch (3) are thyristor Q2, and thyristor Q2 positive terminal and resistance R2 connect Connect, thyristor Q2 negative pole end is connect with ground wire, the one end capacitor C2 respectively, the capacitor C2 other end respectively with thyristor Q2 gate terminal, Ground line current switch driver (10) connection.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201920053361.0U CN209250221U (en) | 2019-01-14 | 2019-01-14 | Low load current automatic detection's earth-leakage protector |
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| CN201920053361.0U CN209250221U (en) | 2019-01-14 | 2019-01-14 | Low load current automatic detection's earth-leakage protector |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109599831A (en) * | 2019-01-14 | 2019-04-09 | 陈劲游 | Low load current automatic detection's earth-leakage protector |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109599831A (en) * | 2019-01-14 | 2019-04-09 | 陈劲游 | Low load current automatic detection's earth-leakage protector |
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