GB2527179A - Residual current protection device - Google Patents
Residual current protection device Download PDFInfo
- Publication number
- GB2527179A GB2527179A GB1505324.2A GB201505324A GB2527179A GB 2527179 A GB2527179 A GB 2527179A GB 201505324 A GB201505324 A GB 201505324A GB 2527179 A GB2527179 A GB 2527179A
- Authority
- GB
- United Kingdom
- Prior art keywords
- line
- rod
- rectification
- protective earth
- zener diode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/26—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents
- H02H3/32—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors
- H02H3/325—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors involving voltage comparison
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/26—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents
- H02H3/32—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors
- H02H3/33—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors using summation current transformers
- H02H3/338—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors using summation current transformers also responsive to wiring error, e.g. loss of neutral, break
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/26—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents
- H02H3/32—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors
- H02H3/34—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors of a three-phase system
- H02H3/347—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors of a three-phase system using summation current transformers
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
A residual current protection device (RCD) comprising multiple means of rectifying current (D1, D2, D3) and internal circuitry of the RCD that is connected to a phase line L3, neutral line N and protective earth line PE, where a Zener diode Z1 is provided between the rectification means and the internal circuitry so that the protective earth (PE) can only be put into a conducting state when the voltage applied to this line is above a certain threshold. This means that the earth line only conducts when there is a broken neutral line and avoids a situation where the voltage to ground is greater than 0V. The rectification means may be a full bridge or half bridge rectifier, or diodes.
Description
Description
Residual current protection device
Technical field
The present utility model relates to a residual current protection device (ROD) , in particular to au ROD for a TN power distribution system.
Background art
A TN power distribution system is a commonly used low-voltage power distribution system, in which the outer metal casing of an electrical appliance is connected to a protective earth (FE) line. A basic structure of a TN power distribution system is shown in Fig. 1, comprising phase lines Li, L2 and L3, a neutral line N and a protective earth line FE. An electrical appliance App is connected to the phase lines Li, L2 and L3 and neutral line N via an ROD, while an outer casing H of the electrical appliance App is electrically connected to the protective earth line FE.
An ROD is a widely used circuit protection device, used to open a circuit breaker inside an appliance when the appliance develops a current leakage fault, in order to cut off the power supply from the power distribution system to the electrical appliance App, and thereby prevent electrocution. The ROD's own power supply is also taken from the power distribution system, e.g. from the phase line L3 and neutral line N as shown in Fig. 1. If the neutral line N breaks, the ROD itself will lose its power supply, and therefore be unable to serve the function of protecting the electrical appliance App. To prevent the occurrence of such a fault, RODs are usually connected to the protective earth line FE via a conducting wire FE. Thus, when the neutral line N breaks, the protective earth line FE can replace the neutral line N, so that the ROD can still form a complete electrical circuit together with phase line L3 and the protective earth line FE, and the ROD itself will not lose its power supply; therefore the ROD can still operate normally, to protect the electrical appliance App.
Normally, It is desirable for the N line alone to be in a conducting state, with the FE line in a non-conducing state.
This is because, if the FE line is in a conducting state, its current will flow to ground via the FE line. However, with regard to the PR line, if the current flowing on the FE line is too large, then the PR line will not be an equipotential body, and the voltage to ground on the FE line will be greater than 0 V. But the FE line is also connected to the outer casing of the electrical appliance, so the result will be that the voltage to ground of the outer casing of the electrical appliance is greater than 0 V. Therefore it is desirable for the FE line to be put into a conducting state only when a line breakage fault occurs on the N line. However, in practical applications, ROD circuits in the prior art will often develop problems, causing the FE line to enter a conducting state when no line breakage fault has occurred on the N line.
Content of the utility model The object of the present utility model is to provide an ROD, which puts the FE line into a conductive state only when a line breakage fault occurs on the N line, and thereby prevents the voltage to ground on the PE line from being greater than 0 V. The present utility model provides an ROD, comprising: a rectification means, comprising multiple rectification elements; and an internal circuit, connected to a phase line, a neutral line and a protective earth line of a power distribution system via the multiple rectification elements in the rectification means, wherein a Zener diode is provided between the rectification means and the internal circuit, in a circuit corresponding to a rectification element correspocding to the protective earth line amongst the multiple rectification elements, such that the protective earth line can only be put into a conducting state when a voltage applied to the protective earth line is greater than & threshold. This significantly increases the voltage at which the protective earth line begins to conduct, ensuring that the protective earth line will not be put into a conducting state when the neutral line is not broken, and thereby avoiding a situation where the voltage to ground on the protective earth line is greater than 0 V. The ROD provided according to the present utility model, wherein the rectification means is a rectification bridge.
The ROD provided according to the present utility model, wherein the rectification bridge is a full bridge or a half bridge.
The ROD provided according to the present utility model, wherein the rectification elements are diodes.
The ROD provided according to the present utility model, wherein the connection from the internal circuit to the protective earth line is accomplished by a conducting wire, with the Zener diode disposed on the condllcting wire.
The ROD provided according to the present utility model, wherein the Zener diode (Zi, Zil, Z12) is connected in series with a rectification element corresponding to the protective earth line amongst the multiple rectification elements, thereby significantly increasing the voltage at which the protective earth line begins to conduct.
The ROD provided according to the present utility model, wherein a switch is further provided between the rectification means and the internal circuit, in a circuit corresponding to a rectification element corresponding to the protective earth line amongst the multiple rectification elements, with the switch and the Zener diode being cor±ined such that the protective earth line can only be put into a conducting state when a voltage applied to the protective earth line is greater than a threshold.
The ROD provided according to the present utility model, wherein the Zener diode controls the switch and thereby controls whether the protective earth line conducts. Since the current in the protective earth line mainly flows Through the switch, damage to the Zener diode by large currents can be prevented, with larger currents being permitted to flow on the protective earth line.
The ROD provided according to the present utility model, wherein the switch is a bipolar junction transistor, MOSFET or IGBT.
The ROD provided according to the present utility model, wherein the Zener diode is a transient voltage suppression diode, to increase response speed.
The ROD provided according to the present utility model, wherein the ROD is used in a TN power distribution system.
The ROD provided according to the present utility model, wherein when a line breakage fault occurs on the neutral line, the protective earth line replaces the neutral line, forming an electrical circuit together with the internal circuit and the phase line.
In the ROD provided in the present utility model, the voltage at which the FE line begins to conduct can be significantly increased, ensuring that the FE line will not be put into a conducting state when the N line is not broken, and thereby avoiding a situation where the voltage to ground on the FE line is greater than 0 V.
Description of the accompanying drawings
The following accompanying drawings are intended merely to illustrate and explain the present utility model schematically, without defining the scope thereof.
Fig. 1 shows the basic structure of a TN power distribution system; Fig. 2 shows a circuit diagram of an ROD's own power supply circuit; Fig. 3 shows an ROD circuit diagram after line impedances have been taken into account; Fig. 4 is a schematic diagram of the circuit structure of an ROD provided by the present utility model; Fig. 5 is a schematic diagram of the circuit structure of another ROD provided by the present utility model; Fig. 6 is a schematic diagram of the circuit structure of another ROD provided by the present utility model; Fig. 7 is a schematic diagram of the circuit structure of another ROD provided by the present utility model.
Particular embodiments Fig. 2 shows a circuit diagram of an ROD's own power supply circuit. For the sake of clarity, Fig. 2 only shows the circuit part of the ROD, omitting mechanical apparatus such as switches. As Fig. 2 shows, the ROD comprises: a rectification bridge R formed by diodes Dl, D2 and D3; a diode D4 connected in series with diode D3; and an internal oircuit C of the ROD, for realizing the functions of the ROD. The phase line L3 and neutral line N (N line) supply power to the internal circuit C of the ROD via the rectification bridge R. In addition, the ROD is further connected to a protective line FE (FE line) via an FE line, so that the FE line replaces the N line when the N line breaks, preventing the ROD itself from losing its power supply. The FE line is connected to a node Ui between diode D2 on the neutral line N and the internal circuit 0, and connects diodes P3 and D4 in series.
Normally, it is desirable for the N line alone to be in a conducting state, with the FE line in a non-conducning state.
This is because, if the FE line is in a conducting state, its current will flow to ground via the FE line. However, with regard to the PE line, if the current flowing on the FE line is too large, then the FE line will not be an eguipotential body, and the voltage to ground on the FE line will be greater than 0 V. But the FE line is also connected to the outer casing of the electrical appliance, so the result will be that the voltage to ground of the outer casing of the electrical appliance is greater than 0 V. Therefore it is desirable for the FE line to be put into a conducting state only when a line breakage fault occurs on the N line.
As Fig. 2 shows, in order for, under normal conditions, the N line alone to be in a conducting state with the FE line in a non-conducting state, diode D4 is provided on the FE line in addition to diode D3 which corresponds to diode D2, to increase the voltage at which the FE line begins to conduct. Under such conditions, if the FE line is in a conducting state, then the voltage UFE at node UT is equal to the voltage drop across diodes D3 and D4, i.e. 1.4 V. If the N line is in a conducting state, then the voltage UN at node UT is equal to The voltage drop across diode D2, i.e. 0.7 V, which is less than the voltage UFE at node Ui when the FE line is in a conducting state. Therefore, according to circuit principles, the N line alone is in a conducting state, while the FE line is in a non-conducting state. It can be seen that the provision of an additional diode 124 on the FE line allows the N line alone to be in a conducting state under normal conditions, with the FE line in a non-conducting state. When the N line breaks, the PE line enters a conducting state, and the ROD forms a complete electrical circuit via node Ul together with the FE line and PE line, so that the ROD itself will not lose its power supply.
However, the ROD circuit shown in Fig. 2 will often develop problems, causing the FE line to enter a conducting state when no line breakage fault has occurred on the N line. This is because the effect of the line impedances of the FE line and N line has been ignored. Fig. 3 shows an ROD circuit diagram after the line impedances of the FE line and N line have been taken into account, wherein the line impedance of the FE line is eguivalent to a resistance RFE, and the line inpedance of the N line is eguivalent to a resistance RN.
Once the line impedance of the FE line and the line impedance of the N line are taken into account, if the FE line is in a conducting state, then the voltage U at node Ul is equal to the voltage drop across diodes 123 and 124 added to the voltage drop across the resistance RFE, i.e. UFE = 1.4 V + FE x RFE, where FE is the current in the FE line when the FE line is in a conducting state. If the N line is in a conducting state, then the voltage UN at node Ui is equal to the voltage drop across diode 122 added to the voltage drop across the resistance RN, i.e. UN = 0.7 V + N x RN, where N is the current in the N line when the N line is in a conducting state. If N x RN -FE x R > 0.7 V, then UN > UFE, in which case, as is clear from the above analysis, the FE line will be put into a conducting state without the N line being in a conducting state. As stated above, if the FE line is in a conducting state then the voltage to ground on the PE line will be greater than 0 V, so that the voltage to ground of the outer casing of the electrical appliance will be greater than 0 V. Embodiment 1 This embodiment provides an RCD for a TN power distribution system, with the circuit structure shown in Fig. 4, comprising: an internal circuit C of the ROD, for realizing the functions of the ROD; a rectification bridge R, formed by diodes Dl, D2 and D3, wherein a phase line L3 is connected to the internai circuit C of the ROD via diode Dl in the rectification bridge R, while an N line is connected to the internal circuit C via diode D2 in the rectification bridge R; in addition, the internal circuit C is also connected to a FE line via an FE line, so that the FE line replaces the N line when the N line breaks, preventing the ROD itself from losing its power supply; the FE line has one end connected to the FE line, and another end connected to a node US between the N line and the internal circuit C; a Zener diode Zl, connected on the FE line in series with diode D3 in the rectification bridge R, and having a breakthrough voltage lJz of 15 V. In Fig. 4, the line impedance of the FE line is eguivalent to a resistance R, while the line impedance of the N line is equivalent to a resistance RN. If the FE line is in a conducting state, then the voltage U at node 111 is equal to the voltage drop across diode D3 and the Zener diode Z1 added to the voltage drop across the resistance RFE, i.e. UFE = 0.7 V + Uz + FE X RFE, where Uz is the breakdown voltage which puts the Zener diode 11 into a conducting state, approximately equal to the voltage drop across the Zener diode 11 when it is in the conducting state, and FE is the current in the FE line when the FE line is in a conducting state. If the N line is in a conducting state, then the voliage UN at node Ui is eqilal to the voltage drop across diode D2 added to the voltage drop across the resistance RN, i.e. UN = 0.7 V + N x RN, where 1N is the current in the N line when the N line is in a conducting state.
Uz is generally relatively large (e.g. 15 V in this embodiment), much larger than the value of N x RN -FE X RFE, therefore even with the effect of the line impedance RFE of the FE line and the line impedance RN of the N line, t can be guaranteed that UFE > UN, so as to ensure that the N line will be in a conducting state without the FE line being put into a conducting state.
Thus, in the ROD provided in this embodiment, the voltage at which the FE line begins to conduct is increased significantly by providing a Zener diode Zi with a relatively high breakdown voltage Uz on the FE line, thereby ensuring that the FE line will not be put into a conducting state when the N line is not broken, so as to avoid a situation where the voltage to ground on the PE line is greater than 0 V, and reducing the safety hazard.
Embodiment 2 This embodiment provides an ROD for a TN power distribution system, with the circuit structure shown in Fig. 5. The structure of the ROD provided in this embodiment is essentially the same as the circuit structure of the ROD in Fig. 4, the difference being that the rectification bridge R employed in the ROD in embodiment 1 is a half bridge, whereas the rectification bridge R employed in this embodiment is a full bridge, and two Zener diodes are used accordingly. The structure of such a full-bridge rectification bride R can provide a higher power.
-10 -As Fig. 5 shows, the rectification bridge R employed in the RCD of this embodiment is formed by diodes Dli, Di2, D21, D22, D31 and D32. Diodes Dli and Di2 are connected to the phase line L3, diodes D2l and P22 are conneoted to the N line, and diodes D3l and D32 are connected to the FE line. Corresponding to the full-bridge rectification bridge R, two Zener diodes Zil and Z12 are provided in the RCD provided in this embodiment, connected on the FE line in series with diodes D3l and D32, respectively, and are used to increase the voltage at which the FE line begins to conduct, thereby ensuring that the FE line will not be put into a conducting state when the N line is not broken.
Embodiment 3 This embodiment provides an RCD for a TN power distribution system, with the circuit structure shown in Fig. 6. The structure of the RCD provided in this embodiment is essentially the same as the circuit structure of the RCD in Fig. 4, the difference being that in this embodiment, a Zener diode Z2 and a switch Qi are provided in the FE line, to increase the voltage at which the FE line begins to conduct.
The Zener diode Z2 has one electrode connected to the FE line, and another end connected to a control electrode of the switch Qi (e.g. the gate of a MOSFET or the base of a bipolar junction transistor) , for the purpose of controlling whether the switch Qi conducts. The two electrodes of the switch Ql other than the control electrode (e.g. the source and drain of a MOSFET or the collector and emitter of a bipolar junction transistor) are connected in series in the FE line. Only when the voltage across the Zener diode Z2 reaches the breakdown voltage liz thereof, will the Zener diode Z2 enter a conducting state, thereby turning on the switch QL and putting the FE line into a conducting state. Since the threshold voltage Uz of the Zener diode is generally relatively large (e.g. 15 V in this embodiment) , the voltage at which the FE line begins to conduct -11 -can be much larger than the vcltage at which the N line begins to conduct, so as to ensure that, when no line breakage fault has occurred on the N line, the N line will be in a conducting state without the FE line being in a conducting state.
In addition, in this embodiment, the current in the FE line mainly flows through the switch Qi, not through the Zener diode Z2. Since the current that the switch Qi can withstand is much greater than the current of the Zener diode Z2, damage to the Zener diode by large currents can be prevented in this embodiment, with larger currents being permitted to flow on the FE lime.
In this embodiment, the Zener diode Z2 is used to control the switch Ql on the FE line and thereby control whether the FE line conducts. Since the breakdown voltage Uz of the Zener diode Z2 is relatively large, the voltage at which the FE line begins to conduct is increased significantly. In other embodiments according to the present utility model, the switch Qi may also be a combination of multiple switches. Those skilled in the art can make various selections flexibly as required. The present utility model can be realized as long as these combinations of switches can control whether The FE line conducts under the control of the Zener diode.
Embodiment 4 This embodiment provides an ROD for a TN power distribution system, with the circuit structure shown in Fig. 7. The structure of the ROD provided in this embodiment is essentially the same as the circuit structure of the ROD in Fig. 5, as both employ a full-bridge rectification bridge R, the difference being that in this embodiment, as in embodiment 3, a combination of a Zener diode and a switch (the combination of a Zener diode Z21 and a switch Qil, and the combination of a Zener diode Z22 and a switch Q12) is provided to increase the voltage at which the FE line begins to conduct.
-12 -In this embodiment, the current in the PE line mainly flows through switches Qil and Q12, not through Zener diodes Z21 and Z22. Since the current that the switches Qil and Ql2 can withstand is much greater than the current of the Zener diodes Z2l and Z22, damage to the Zener diodes by large currents can be prevented in this embodiment, with larger currents being permitted to flow on the FE line.
In other embodiments according to the present utility model, the switches Qil and Q12 may also each be a combination of multiple switches. Those skilled in the art can make various selections flexibly as reguired. The present utility model can be realized as long as these combinations of switches can control whether the FE line conducts under the control of the corresponding Zener diode.
According to an embodiment of the present utility model, the switch may comprise a bipolar junction transistor, MOSE'ET, IGBT, etc. According to an embodiment of the present utility model, the rectification bridge R may also be another form of rectification means.
The Zener diode referred to in the present utility model is a diode based on the Zener breakdown effect, including a reference voltage Zener diode, transient voltage suppression diode (TVS), etc. In the present utility model, there is no reguirement regarding voltage stabilization properties; instead, it is desirable to increase response speed. Therefore a transient voltage suppression diode (TVS) with a fast response speed is preferably used in the present utility model.
The RCD according to the present utility model is explained in the embodiments above using a TN system as an example. However, those skilled in the art will understand that the RCD according -13 -to the present utility model could also be used in other types of power distribution system having an N line and a FE line.
It should be understood that although the description herein is based on various embodiments, it is by no means the case that each er±odiment contains just one independent technical solution. Such a method of presentation is adopted herein purely for the sake of clarity. Those skilled in the art should consider the description in its entirety. The technical solutions in the various embodiments could also be suitably combined to form other embodiments capable of being understood by those skilled in the art.
The above embodiments are merely particular schematic embodiments of the present utility model, which are not intended to define the scope thereof. Any equivalent changes, modifications or combinations made by those skilled in the art without departing from the concept and principles of the present utility model should be included in the scope of protection of the present utility model.
List of labels in the accompanying drawings Residual current protection device ROD; diodes Dl, D2, D3, D4, Dil, Di2, D21, D22, D3i, D32; rectification bridge R; internal circuit C; phase lines Li, L2, L3; neutral line N; protective earth line FE; node Dl; Zener diodes El, Eli, 112, 12, 121, 122; N line equivalent resistance R5; FE line equivalent resistance RFE; switches Qi, Qil, Q12
Claims (12)
- -14 -Claims 1. A residual current protection device (ROD), comprising: a rectification means (R) , comprising multiple rectification elements (Dl, D2, D3, Dli, D12, D21, D22, D31, D32); and an internal circuit (C) , connected to a phase line (Li, L2, L3), a neutral line (N) and a protective earth line (PE) of a power distribution system via the multiple rectification elements in the rectification means (R) characterized in that a Zener diode (Zl, Zl1, Zi2, Z2, Z21, Z22) is provided between the rectification means (R) and the internal circuit (C) , in a circuit corresponding to a rectification element corresponding to the protective earth line (PE) amongst the multiple rectification elements, such that the protective earth line (PE) can only be put into a conducting state when a voltage applied to the protective earth line (PE) is greater than a threshold.
- 2. The ROD as claimed in claim 1, characterized in that the rectification means (R) is a rectification bridge.
- 3. The ROD as claimed in claim 2, characterized in that the rectification bridge is a full bridge or a half bridge.
- 4. The ROD as claimed in claim 1, characterized in that the rectification elements (Dl, D2, D3, Dli, Dl2, D21, D22, D31, D32) are diodes.
- 5. The ROD as claimed in claim 1, characterized in that the connection from the internal circuit (0) to the protective earth line (PE) is accomplished by a conducting wire (FE), with the Zener diode (Zi, Zil, Zi2, Z2, Z21, Z22) disposed on the conducting wire (FE)
- 6. The ROD as claimed in claim 1, characterized in that the Zener diode (Zl, Zn, Z12) is connected in series with a -15 -rectification element corresponding to the protective earth line (PE) amongst the multiple rectification elements.
- 7. The ROD as claimed in claim 1, characterized in that a switch (Qi, Qli, Q12) is further provided between the rectification means (R) and the internal circuit (0) , in a circuit corresponding to a rectification element corresponding to the protective earth line (PE) amongst the multiple rectification elements, with the switch (Ql, Qil, Q12) and the Zener diode (Z2, Z21, Z22) being combined such that the protective earth line (PE) can only be put into a conducting state when a voltage applied to the protective earth line (PE) is greater than a threshold.
- 8. The ROD as claimed in claim 7, characterized in that the Zener diode (12, 121, 122) controls the switch (Qi, Qil, Qi2) and thereby controls whether the protective earth line (PE) conducts.
- 9. The ROD as claimed in claim 7, characterized in that the switch is a bipolar junction transistor, MOSFET or IGBT.
- 10. The ROD as claimed in claim 1, characterized in that the Zener diode (Zi, Zil, Z12, Z2, Z21, Z22) is a transient voltage suppression diode.
- 11. The ROD as claimed in claim 1, characterized in that the ROD is used in a TN power distribution system.
- 12. The ROD as claimed in claim 1, characterized in that when a line breakage fault occurs on the neutral line (N) , the protective earth line (PE) replaces the neutral line (N) forming an electrical circuit together with the internal circuit and the phase line (Li, L2, L3)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420224086.1U CN203983940U (en) | 2014-05-04 | 2014-05-04 | Earth leakage protective device |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB201505324D0 GB201505324D0 (en) | 2015-05-13 |
| GB2527179A true GB2527179A (en) | 2015-12-16 |
| GB2527179B GB2527179B (en) | 2021-02-10 |
Family
ID=51981356
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1505324.2A Active GB2527179B (en) | 2014-05-04 | 2015-03-27 | Residual current protection device |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN203983940U (en) |
| GB (1) | GB2527179B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0154450A1 (en) * | 1984-02-23 | 1985-09-11 | Delta Electrical (Holdings) Limited | Earth leakage protective circuit |
| GB2178916A (en) * | 1985-06-22 | 1987-02-18 | Ashley Accessories Ltd | Detecting abnormal neutral line |
| GB2201055A (en) * | 1984-07-30 | 1988-08-17 | Technology Res Corp | Ground fault current interrupter circuit with additional protection |
| GB2244398A (en) * | 1990-05-25 | 1991-11-27 | Mk Electric Ltd | Test circuit for residual current device |
| GB2268011A (en) * | 1992-06-18 | 1993-12-22 | Shakira Ltd | Residual current device |
| GB2277646A (en) * | 1993-04-27 | 1994-11-02 | Shakira Ltd | Mains neutral fault detector |
| GB2518733A (en) * | 2013-09-05 | 2015-04-01 | Siemens Ag | Neutral line breakage detection circuit, method and corresponding residual current circuit breaker |
-
2014
- 2014-05-04 CN CN201420224086.1U patent/CN203983940U/en not_active Expired - Fee Related
-
2015
- 2015-03-27 GB GB1505324.2A patent/GB2527179B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0154450A1 (en) * | 1984-02-23 | 1985-09-11 | Delta Electrical (Holdings) Limited | Earth leakage protective circuit |
| GB2201055A (en) * | 1984-07-30 | 1988-08-17 | Technology Res Corp | Ground fault current interrupter circuit with additional protection |
| GB2178916A (en) * | 1985-06-22 | 1987-02-18 | Ashley Accessories Ltd | Detecting abnormal neutral line |
| GB2244398A (en) * | 1990-05-25 | 1991-11-27 | Mk Electric Ltd | Test circuit for residual current device |
| GB2268011A (en) * | 1992-06-18 | 1993-12-22 | Shakira Ltd | Residual current device |
| GB2277646A (en) * | 1993-04-27 | 1994-11-02 | Shakira Ltd | Mains neutral fault detector |
| GB2518733A (en) * | 2013-09-05 | 2015-04-01 | Siemens Ag | Neutral line breakage detection circuit, method and corresponding residual current circuit breaker |
Also Published As
| Publication number | Publication date |
|---|---|
| GB201505324D0 (en) | 2015-05-13 |
| GB2527179B (en) | 2021-02-10 |
| CN203983940U (en) | 2014-12-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI622240B (en) | Solid state fault current limiting device,method and system for limiting fault current | |
| CN207542770U (en) | A kind of DC over-voltage protection circuit and the power grid power supply voltage-stabilized power supply circuit for including it | |
| US10270240B2 (en) | Surge protective device with abnormal overvoltage protection | |
| CN205265251U (en) | A device for overvoltage protection in power supply line | |
| KR20130081727A (en) | Power supply apparatus including a function of protecting over-voltage | |
| CN205304240U (en) | Control circuit is prevented joining conversely by high -power direct current | |
| CN104682338A (en) | Protection circuit and lighting equipment | |
| EP3012853B1 (en) | Electrical safety device miswire detection | |
| GB2527179A (en) | Residual current protection device | |
| KR101302123B1 (en) | Earth leakage breaker of automatic recovery type | |
| CN101877473B (en) | Protection circuit in surge protector used for high-definition camera | |
| AU2015201523B2 (en) | Residual current protection device | |
| CN210468782U (en) | Power line leakage protection device, electric connection equipment and electrical appliance | |
| CN104283190A (en) | Device and method for protecting against leakage currents | |
| KR20130026295A (en) | Cut out switch having lightning arrester | |
| CN203301121U (en) | Protective circuit capable of adjusting rated voltage and rated current | |
| KR100995996B1 (en) | Electronic switch operating of switched-mode power supply | |
| CN205846698U (en) | There is the RCCB of overvoltage protection and low-voltage protection | |
| CN203522174U (en) | Lightning protection device for single-phase leakage switch | |
| JP2014176267A (en) | Load control device | |
| AU2020449613B2 (en) | Ramez very smart earthing system, short circuit and overcurrent protection | |
| RU124453U1 (en) | PROTECTIVE CIRCUIT BREAKER (OPTIONS) | |
| CN102723692A (en) | Overcurrent protection circuit with feedback | |
| CN210724190U (en) | Electric leakage circuit breaker with anti-power interference function | |
| CN201674201U (en) | Protection circuit in surge protective device for high definition camera |