EP3850652A1

EP3850652A1 - Relay module

Info

Publication number: EP3850652A1
Application number: EP19758413.9A
Authority: EP
Inventors: Stefan Benk; Ralf Hoffmann; Christian Adam
Original assignee: Phoenix Contact GmbH and Co KG
Current assignee: Phoenix Contact GmbH and Co KG
Priority date: 2018-09-12
Filing date: 2019-08-26
Publication date: 2021-07-21
Also published as: JP2022500826A; US20210313131A1; BE1026605B1; WO2020052947A1; BE1026605A1; JP7185768B2

Abstract

The invention relates to an electromagnetic relay module (100) comprising a first circuit branch (119) having a first capacitor (115) and a first relay (103) connected in series with the first capacitor (115), a second circuit branch (121) having a second capacitor (117) and a second relay (105) connected in series with the second capacitor (117), and a switch element (125) arranged between the first circuit branch (119) and the second circuit branch (121) and having a first switch status and a second switch status. In the first switch status of the switch element (125), the first circuit branch (119) and the second circuit branch (121) are connected in parallel. In the second switch status of the switch element (125), the first relay (103) and the second relay (105) are connected in series. When the relay module (100) is switched on, the switch element (125) is designed to switch from the first switch status into the second switch status in order to increase the total resistance of the relay module (100).

Description

Relay module

The present invention relates to a relay module, in particular a

electromagnetic relay module, and an arrangement with a

electromagnetic relay module.

With electromagnetic relays, there is the problem of heating due to high coil currents, which are required to pull the armature from an open position into a holding position and to close the relay. A minimal response flow is necessary to tighten the anchors. To hold the armature in the closed state, a lower holding flow is necessary in comparison to this. Since a stronger magnetic field and thus a greater magnetic flux through the excitation coil than for holding the armature in the holding position is required for the attraction, solutions that are magnetic are desirable

Flooding the excitation coil after tightening the armature in the holding position and for the period in which the armature is held in the holding position, and thus the power and consequently the heating of the relay, for the period in which the relay is kept closed to reduce. A known solution consists in assigning pulse width modulation (PWM) to the supply voltage and in this way reducing the coil current to an advantageous value for the desired period of time. For PWM control, however, are complex

microelectronic components and correspondingly complex switching architectures are required. The PWM can also cause electromagnetic effects on the environment, which can be undesirable.

It is an object of the present invention to provide an improved concept for a relay module.

This object is solved by the subject matter of the independent claims. Advantageous embodiments of the invention are the subject of the dependent claims, the description and the accompanying figures.

The disclosure is based on the knowledge that the above task is solved by a relay module that enables an increase in the

Total resistance of the relay module after the relays have been fully tightened, in particular the relay coils of both relays of the relay module, with unchanged supply voltage, in particular constant and stable applied voltage, to reduce the coil current and thus to lower the relay power or the electrical power and thus the heat development or the heat loss power.

According to a first aspect, the task is performed by an electromagnetic

Relay module solved, with a first circuit branch having a first capacitor and a first relay connected in series with the first capacitor, a second circuit branch having a second capacitor and a second relay connected in series with the second capacitor, a switching element which between the is arranged first circuit branch and the second circuit branch and has a first switching state and a second switching state. In the first switching state of the switching element, the first circuit branch and the second circuit branch are arranged in a parallel connection. In the second

Switching state of the switching element, the first relay and the second relay are arranged in a series circuit. The switching element is designed in

Switching on the relay module to switch from the first switching state to the second switching state in order to increase the overall resistance of the relay module.

This has the technical advantage that a relay module can be provided, the coil power of the first relay or second relay automatically from a pull-in power, which must be provided to pull the armature from an open position to the holding position, to a lower holding power , which has to be applied in order to hold the anchor in the holding position, is reduced as soon as the first anchor and the second anchor are fully drawn into the holding position. The stop position of the

Relay module can be defined in such a way that the first armature of the first relay and the second armature of the second relay are closed, that is to say both relays have pulled through completely.

The design of the present relay module with two interconnected relays enables the overall resistance of the relay module to be changed, in particular increased, by converting the circuit arrangement of the two relays from a parallel connection into a series connection of the relays.

By switching the parallel connection of the first circuit branch and the second circuit branch into the series connection of the first relay and the second Relay, the total resistance of the relay module, in particular a combination of the first relay and the second relay, is thus increased.

If the supply voltage remains unchanged, the increase in the total resistance of the series-connected first relays and second relays in turn leads to one

Reduction in flowing through the first relay and the second relay

Coil currents. A reduced coil current in turn leads to a reduction in the magnetic flux through the respective relays and, associated therewith, to a reduction in the magnetic field in the respective relay.

Because of the low impedance of the first capacitor and the second

Capacitor for the period in which the switching element in the first

Switching state is located, the first and the second circuit branch are arranged in parallel and the first capacitor and the second capacitor are charged, are resistors of the first capacitor and the second capacitor for the

Determination of the total resistance for this period is negligible.

The first capacitor and the second capacitor are again such

dimensioned that a full charge of the first capacitor and the second capacitor corresponds to a complete tightening of the armature in the holding position. The dimensioning can depend on the operating voltage, the coil resistance, i.e. the internal resistance, and the inductance. In this way, reaching the necessary flooding to achieve the working state of the

Relay module can be guaranteed. The capacitors and components of the switching element can be designed in such a way that the switchover occurs without an additional switching pulse. The holding value is typically 50%, conservative at 60% nominal voltage.

If the coil voltage becomes zero again, the switching element switches again from the second switching state to the first switching state.

A reduction in the heat development of the relays is achieved by reducing the flow and thus reducing the respective coil power of each relay. In the case of components of small size in particular, a reduction in the development of heat is advantageous due to the low thermal capacity of the components.

In one embodiment, the relay module has a stop position in which a first armature is attracted by the first relay and in which a position is drawn by the second relay second armature is attracted, and wherein the switching element is designed to change from the first switching state to the second switching state as soon as the

Relay module has taken the stop position

Tightening the anchors requires a higher flow, in particular an initial flow, than holding the anchors by the respective relay. To tighten the anchors a higher power is necessary than to hold the anchors. After the armature has been tightened, the flow through the coils of the relays can be reduced. The switching time of the switching element can therefore be selected so that switching to the series connection of the relays takes place as soon as both anchors are attracted. The current is reduced at the same voltage due to the increased total resistance and the power used is therefore also reduced.

In one embodiment, the first capacitor is formed in the first

Switching state of the switching element to provide the first relay with a first charging current. The second capacitor is designed to provide the second relay with a second charging current in the first switching state of the switching element. The first charging current is suitable for causing the first armature to be pulled and held, and the second charging current is suitable for causing the second armature to be drawn and held.

The charging current of the capacitors can be sufficient to switch the relays. This means that the charging current of the capacitors is sufficient to provide the initial flow for the respective relay. The capacitors can be used to set a switching time for the switching element, which switches when both armatures are attracted.

In one embodiment, the relay module can be electrically connected to a voltage source which is set up to provide a constant voltage, the first circuit branch and the second circuit branch being connectable to the voltage source.

The voltage source can be a DC voltage source that provides a constant voltage. The voltage can be, for example, 12V or 24V and thus operate both relays with a corresponding voltage value. The voltage can also have other values. The level of tension can vary from one Application of the relay module. Due to the voltage source, the current when switching to the series circuit can then be increased due to the then

Overall resistance can be reduced.

In one embodiment, the first capacitor provides the first charging current and the second capacitor provides the second charging current when the constant voltage is applied to the first circuit branch and to the second circuit branch.

The first capacitor and the second capacitor are charged when the constant voltage is applied. The voltage across the capacitors increases. The charging current decreases over time. However, the charging current is sufficient to switch the relays.

In one embodiment, the first switching state of the switching element comprises a high resistance of the switching element in comparison to the resistance of the

Includes switching element in the second switching state and the second switching state of the switching element has a low resistance of the switching element compared to the resistance of the switching element in the first switching state.

A high resistance can limit a current flow through the switching element to such an extent that it can be neglected. If the resistance is reduced, a current flow through the switching element is allowed. This can be seen as a switching operation.

In one embodiment, the switching element comprises a diode, the diode being set up to transition from the first switching state to the second switching state when a forward voltage of the diode is reached.

The switching element is designed here as a diode, which is operated when the two coils are connected in series in the flow direction or forward direction. Switching from parallel to series connection can be done by the

Voltage difference between the first circuit branch and the second circuit branch. This is at least equal to the forward voltage of the diode. This means that a voltage below the forward voltage corresponds to a first switching state and a voltage at the forward voltage or higher corresponds to the second switching state. The forward voltage corresponds to the

Threshold voltage. In particular, the term forward voltage means the voltage which can be read in the diode characteristic diagram if the apparently straight part is extended to the x-axis.

This has the technical advantage that the switching element is easy to manufacture and the switching process runs automatically. The switching process of the switching element, which converts the parallel connection of the first circuit branch and the second circuit branch into the series connection of the first relay and the second relay, begins as soon as the voltage difference between the first

Circuit branch and the second circuit branch at least the

Forward voltage of the diode corresponds. In addition, through the

additional voltage drop across the diode and the series resistor of the

Switching element in the circuit branch between the first circuit branch and the second circuit branch, the current in the series circuit of the first relay and the second relay can be further reduced, so that the heat losses through the first and second excitation coils can also be reduced.

If a diode is used as the switching element, the switching time is determined by the capacitance of the capacitors, i.e. the relay, with a fixed internal resistance and coil dimensions. of the first capacitor and the second capacitor. The switching time results from the voltage difference in the central branch of the circuit. At the beginning, this is equal to the total voltage applied, with zero reactance of the capacitors. By charging the capacitors, the initially negative voltage between the first circuit branch and the second circuit branch is reduced in magnitude, that is to say towards zero. If the voltage becomes positive and greater than the forward voltage of the diode, the diode switches.

In one embodiment, the switching element comprises at least one further diode and / or a series resistor in order to influence the time of the transition from the first switching state to the second switching state.

The switching time can be varied by a plurality of diodes in series and / or in combination with a series resistor to the diode between the first circuit branch and the second circuit branch. That is, the relay module can be adapted so that the switching element switches at a desired time, relative to the switching state of the relays. Due to the additional voltage drop across the diode and the resistor, the current in series connection of the coils can be further reduced. The heat losses can be reduced. The Series resistor can change the diode current when the relay and the

Holding current, i.e. limit the operating current of the relay module in the hold state.

In one embodiment, the switching element comprises a transistor, in particular a bipolar transistor or a field effect transistor, i.e. a MOSFET.

This achieves the technical advantage that the switching element is designed as a robust component with high switching accuracy and switching reliability.

In one embodiment, the transistor is a PNP bipolar transistor, or an NPN bipolar transistor.

This has the technical advantage that after completion of the

Switching process in the series connection of the first and second excitation coils a low excitation current flows. A PNP transistor can reduce the current in the series connection by half compared to the parallel connection. This effect can be enhanced with an NPN transistor and thus the current can be further reduced.

In one embodiment, the transistor is a MOSFET transistor.

In addition, the transistor is de-energized during the switching process, so that the occurrence of power loss during the switching process on the switching element is avoided. High blocking currents can be avoided and voltage peaks can be assessed more precisely by using blocking diodes. The use of a MOSFET is more energy efficient than with another transistor, since no current flows to the control connection of the transistor. Voltage peaks on the coils when the transistor is switched off can also be avoided.

In one embodiment, the transistor is preceded by an RC element and a voltage divider, a time constant being defined via the RC element and the voltage divider.

This achieves the technical advantage that the switching time of the switching element can be matched to the point in time at which the armatures are fully pulled into the holding position, that is, by means of the time constant of the RC element Relay module has entered the holding state. For this purpose, the RC element has a third resistor and a third capacitor. The dimensions of the third resistor and the third capacitor are matched to the first capacitor and the second capacitor. A point in time at which the stop position is reached can thus be determined over the duration of the charging of the first capacitor and the second capacitor. By tuning the dimensioning of the RC element with regard to the ratio of the time constant of the RC element to the duration of the charging of the first capacitor and the second capacitor, it is consequently possible to adjust the switching time of the

Switching element can be reached with the time of fully tightening the armature in the holding position. This gives the technical advantage that voltage peaks at the second excitation coil are avoided.

In one embodiment, the transistor is preceded by a controller, in particular a microcontroller, which is set up as a function of a measured current in the first circuit branch and / or the second

Circuit branch to determine a switching time of the transistor.

A switching point in time can also be adapted by a control, such as a microcontroller, for example in an operation by reprogramming or adjusting the control. An external voltage pulse can be given from the controller to the transistor, which leads to switching. The individual relay currents are measured, i.e. the currents through the relays.

In one embodiment, the controller is set up to provide a switching voltage for switching the switching element when the measured current falls below a predetermined limit value, in particular a predetermined one

Falls below the limit in the first circuit branch or the second circuit branch.

The charging current of the capacitors is monitored here. If it drops to a predetermined limit after a maximum, it can be assumed that the relays have successfully pulled the respective armature. The charging current is also the current that flows through the respective coil in the first circuit branch or second circuit branch. In one embodiment, a first blocking diode is arranged between the first relay and the switching element in order to block a current flow from the switching element to the first relay and a second blocking diode is arranged between the second relay and the switching element in order to block a current flow from the second relay to block the switching element in order to limit a switch-off current.

The blocking diodes can undesirably prevent current flow through the relays. In particular, a cut-off current can be limited here.

In one embodiment, the relay module is a safety relay module to perform a safety-relevant function and the first relay and the second relay are redundant relays.

A safety-relevant function can be a function that affects the safety of a user. For example, a user can be in front of a

Electric shock can be protected.

According to a second aspect, the object is achieved by an arrangement with an electromagnetic relay module of the type described above in an emergency stop switch or a protective door switch or a magnetic switch or with a light grid.

As a result, the safety of the respective component can be kept high and, in addition, the power of the relay module can be reduced as described above.

Further exemplary embodiments are explained with reference to the attached figures. Show it:

Fig. 1 is an equivalent circuit diagram of a relay module according to a

Embodiment;

Fig. 2 is an equivalent circuit diagram of a relay module according to another

Embodiment;

Fig. 3 is an equivalent circuit diagram of a relay module according to another

Embodiment; Fig. 4 is an equivalent circuit diagram of a relay module according to another

Embodiment;

Fig. 5 is an equivalent circuit diagram of a relay module according to another

Embodiment;

6 shows an equivalent circuit diagram of a relay module according to another

Embodiment; and FIG. 7 shows a schematic illustration of an arrangement with a relay module according to an exemplary embodiment.

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which specific embodiments are shown by way of illustration in which the invention may be carried out. It goes without saying that other embodiments can also be used and structural or logical changes can be made without departing from the concept of the present invention. The following detailed

The description is therefore not to be understood in a restrictive sense. Furthermore, it is understood that the features of the various described herein

Embodiments can be combined with one another, unless specifically stated otherwise.

Aspects and embodiments are described with reference to the drawings, wherein like reference characters generally refer to like elements.

1 shows an equivalent circuit diagram of a relay module 100 according to one

Embodiment. The electromagnetic relay module 100 comprises a first relay 103 and a second relay 105. The first relay 103 has a first internal resistance 107 and a first coil 109. The first coil 109 is set up to generate a first magnetic field and to attract a first armature (not shown in the figures) through the first magnetic field. The second relay 105 has a second internal resistance 11 1 and a second coil 1 13. The second coil 1 13 is set up to generate a second magnetic field and through the second

Magnetic field to attract a second anchor (also not shown in the figures). If the first armature is attracted, the first relay 103 is in a hold state. If the second armature is attracted, the second relay 105 is in a hold state. If the first armature and the second armature are both attracted at the same time, the relay module 100 is in a holding state.

The relay module 100 has a first capacitor 115 and a second

Capacitor 117 on. The first capacitor 115 is connected in series with the first relay 103. The first capacitor 115 and the first relay 103 are arranged in a first circuit branch 119. The second capacitor 117 is connected in series with the second relay 105. The second capacitor 1 17 and the second relay 105 are arranged in a second circuit branch 121. The first circuit branch 119 and the second circuit branch 121 are arranged parallel to one another.

The relay module 100 has a voltage source 123. The voltage source 123 is a constant voltage source and is configured to output a constant voltage. That is, the voltage is regulated to a setpoint if

Fluctuations in the voltage provided occur. For example, voltage source 123 provides a constant voltage of 12V. In a further exemplary embodiment, the voltage source 119 provides another constant voltage, for example 24V. The first voltage branch 119 and the second

Voltage branch 121 are electrically connected to voltage source 123.

By applying the constant voltage through the voltage source 123, the first capacitor 115 and the second capacitor 117 are charged. By charging the first capacitor 115, a first charging current flows through the first relay 103. By charging the second capacitor 115, a second charging current flows through the second relay 103.

The first capacitor 115 is dimensioned such that the first charging current is suitable, a magnetic flooding of the first coil and so on

to effect a corresponding magnetic field which is suitable for completely attracting the first armature of the first relay 103 and thus the first relay 103 into the

Stop position. The second capacitor 115 is dimensioned such that the second charging current is suitable for causing a magnetic flooding of the second coil and thus a corresponding magnetic field which is suitable for fully attracting the second armature of the second relay 103 and thus the second relay 103 in to move the stop position. Both capacitors 115, 117 are dimensioned such that the charging current is sufficient, one in the coils 109, 1 13 used

To achieve initial flooding, each of which generates a magnetic field to attract the corresponding anchor.

The relay module 100 has a switching element 125. The switching element 125 is arranged between the first circuit branch 119 and the second circuit branch 121 such that the switching element 125 is arranged between the first relay 103 and the first capacitor 115 and between the second capacitor 119 and the second relay 105. The switching element 125 has a first one

Switching state and a second switching state.

In the first switching state of the switching element 125, the switching element 125 is open or high-resistance in order to prevent current flow from the first relay 103 to the second relay 105 through the switching element 125. Preventing this can be understood to mean that the current flow is interrupted or limited to such an extent that it can be neglected in the normal application of the relay module 100. In the second switching state of the switching element 125, the first circuit branch 119 is electrically connected to the second circuit branch 121 by the switching element 125, so that an electrical current can flow through the switching element 125. The switching element 125 is closed or has a low resistance.

When the switching element 125 is switched to the second switching state, the parallel connection of the first and second circuit branches 101, 102 becomes one

Series connection of the first and second relays 103, 105 connected. That is, in the second switching state of the switching element 125, the first relay 103 and the second relay 105 are electrically connected in series by the switching element 125.

The switching element 125 is set up to switch from the first switching state to the second switching state when the relay module 100 reaches the holding state, that is to say as soon as the first armature and the second armature are attracted.

The first capacitor 115 and the second capacitor 117 are high-impedance at the switching time of the switching element 125 and are not part of the series connection of the first relay 103 and the second relay 105. They thus ensure that a primary current path along the series connection of the first relay 103 and the second relay 105 runs. When the parallel connection of the first and second circuit branches 101, 102 is switched over to connect the first relay 103 and the second relay 105 in series, the total resistance of the first relay 103 and the second relay 105 is increased. This has a reduction in the coil currents, at constant voltage caused by the

Voltage source is ensured, and an associated reduction in the magnetic flux and the magnetic fields of the first relay 103 and the second relay 105 result, whereby the power loss of the relay module 100 can be reduced.

2 shows an equivalent circuit diagram of a relay module 200 according to a further exemplary embodiment. Here, the switching element 125 comprises a diode 201 and a series resistor 203 connected upstream of the diode 201. The time of the

Switching operation of the switching element 125, in which the parallel connection of the first circuit branch 119 and the second circuit branch 121 is transferred to the series connection of the first relay 103 and the second relay 105, to the

Voltage difference between the first circuit branch 119 and the second circuit branch 121 can be coupled. The switching element 125 accordingly switches as soon as the voltage difference between the first circuit branch 119 and the second circuit branch 121 corresponds to the forward voltage of the diode 201.

In a further exemplary embodiment (not shown in the figures), this includes

Switching element 125 a plurality of diodes connected in series. In a further exemplary embodiment, the switching element 125 additionally comprises a plurality of series resistors connected in series. As a result, the time of the switching process of the switching element 125 can be changed compared to the circuit with only one diode 201 and a series resistor 203.

3 shows an equivalent circuit diagram of a relay module 300 according to a further exemplary embodiment. Here, the switching element 125 comprises a transistor 301. In the exemplary embodiment shown, the transistor 301 is a PNP bipolar transistor. In a further embodiment, it is a different transistor, in particular an NPN bipolar transistor.

The transistor 301 is connected via the base connection to a voltage divider 303, which comprises a first resistor 305 and a second resistor 307. The transistor 301 is additionally connected to an RC element 309 via the base connection electrically connected, which comprises a third resistor 31 1 and a third capacitor 313 connected. The switching time of the transistor 301 can be coordinated with the timing of the complete attraction of the first armature and the second armature, ie the dimensioning of the RC element 309 and the first resistor 305 and the second resistor 307 of the voltage divider 303

The switching time of the switching element 125 can be coupled, in particular coupled, to the reaching of the holding state of the relay module 100.

In the exemplary embodiment shown in FIG. 3, the first circuit branch 119 additionally has a first blocking diode 315 and the second circuit branch 121 has a second blocking diode 317. The first blocking diode 315 and the second blocking diode 317 are arranged between the first relay 103 and the first capacitor 115 or the second capacitor 117 and the second relay 105 such that the first blocking diode 315 and the second blocking diode 317 form part of the series circuit with the first Relays 104 and the second relay 105 are when the transistor is in the conducting state and the switching element 103 is thus in the second switching state. In a further exemplary embodiment, one or both blocking diodes 115, 117 can be omitted.

4 shows an equivalent circuit diagram of a relay module 400 according to a further exemplary embodiment. Here, the switching element 125, as described for FIG. 3, is the transistor 301. Likewise, the first circuit branch 119 has the first blocking diode 315 and the second circuit branch 121 has the second blocking diode 317.

However, instead of the voltage divider 303 and the RC element 309 for controlling the switching time of the transistor 301, a controller 401, in particular a microcontroller, is provided, which is connected to the base connection of the transistor 301 and is set up to transmit a switching signal to the via an output of the controller Base terminal of transistor 301 to send. This can

Switching element 125, i.e. the transistor 301, from the first switching state to the second switching state.

To determine the point in time for the switching of the switching element 125, the circuit according to the exemplary embodiment shown in FIG. 4 comprises one

Current measuring device 403. The current measuring device 403 does not include one current measuring resistor shown. In a further exemplary embodiment, the current is measured contactlessly using a current clamp.

If the measured current reaches a limit value stored in the controller, the controller 401 generates a control signal and sends the control signal via an output of the controller 401 to the transistor 301 in order to send the transistor 301

Switching and switching the switching element 125 from the first switching state to the second switching state.

5 shows an equivalent circuit diagram of a relay module 500 according to a further exemplary embodiment. The relay module 500 according to the exemplary embodiment from FIG.

5 corresponds to the relay module 300 of the exemplary embodiment from FIG. 3. However, the transistor 301 is a field effect transistor, in particular a metal oxide semiconductor field effect transistor, or MOSFET for short.

The voltage divider 303 and the RC element 309 are in this case connected to the gate connection of the MOSFET in order to adapt the switching instant of the switching element 125 to the transition of the relay module 100 into the holding state.

6 shows an equivalent circuit diagram of a relay module 600 according to a further exemplary embodiment. The relay module 600 according to the exemplary embodiment from FIG.

6 corresponds to the relay module 400 of the exemplary embodiment from FIG. 4. However, the transistor 301 is a field effect transistor, in particular a metal oxide semiconductor field effect transistor, in short MOSFET.

The controller 401 is connected to the gate connection of the MOSFET in order to adapt the switching time of the switching element 125 to the transition of the relay module 100 into the holding state.

7 shows an arrangement 700. The arrangement 700 comprises the relay module 100 and an emergency stop switch 701. In a further exemplary embodiment, one of the relay modules 200, 300, 400, 500 or 600 is installed. In another

The exemplary embodiment comprises the arrangement 700, the relay module 100 and a protective door switch or a magnetic switch or a light grid.

The relay module 100 is arranged such that a safety-relevant function of the arrangement 700 can be fulfilled by the relay module 100. In the shown In the exemplary embodiment, the relay module 100 is actuated by the emergency stop switch 701 in order to interrupt a circuit 703. Circuit 703 is only partially shown in FIG. 7 for reasons of clarity. In particular, the circuit 703 can comprise further components in parts not shown or can be connected to machines. Here, the first relay 103 and the second relay 105 interrupt the circuit 703 redundantly. This ensures that the circuit 703 is interrupted even if one of the two relays 103, 105 malfunctions, such as a jamming armature.

Reference list

100, 200, 300 relay module

400, 500, 600 relay module

103 first relay

105 second relay

107 first internal resistance 109 first coil

1 1 1 second internal resistance 113 second coil

115 first capacitor 117 second capacitor 119 first circuit branch 121 second circuit branch 123 voltage source 125 switching element

201 diode

203 series resistor

301 transistor

303 voltage divider 305 first resistor 307 second resistor 309 RC element

31 1 third resistor 313 third capacitor 315 first blocking diode 317 second blocking diode 401 control

403 current measuring device 700 arrangement

701 emergency stop switch 703 circuit

Claims

PATENT CLAIMS

1. Electromagnetic relay module (100, 200, 300, 400, 500, 600), with: a first circuit branch (119) which has a first capacitor (115) and a first relay (103) connected in series with the first capacitor (115) comprises a second circuit branch (121), which has a second capacitor (1 17) and a second relay (105) connected in series with the second capacitor (117), a switching element (125) which is connected between the first circuit branch (119) and the second circuit branch (121) is arranged and has a first switching state and a second switching state, wherein in the first switching state of the switching element (125) the first circuit branch (1 19) and the second circuit branch (121) are arranged in a parallel circuit, and wherein in second switching state of the switching element (125) the first relay (103) and the second relay (105) are arranged in a series circuit, and wherein the switching element (125) is formed in the switch-on process de s relay module (100, 200, 300, 400, 500, 600) from the first switching state to the second

Switch switching state to increase the total resistance of the relay module (100, 200, 300, 400, 500, 600).

2. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to claim 1, wherein the relay module (100, 200, 300, 400, 500, 600) has a stop position in which the first relay (103) a first armature is attracted and in which a second armature is attracted by the second relay (105), and wherein the switching element (125) is designed to change from the first switching state to the second switching state as soon as the relay module (100, 200, 300, 400, 500, 600) has taken the stop position.

3. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to claim 2, wherein the first capacitor (1 15) is formed in the first

Switching state of the switching element (125) to provide the first relay (103) with a first charging current and the second capacitor (117) is designed to provide the second relay (105) with a second one in the first switching state of the switching element (125) To provide charging current, wherein the first charging current is suitable for causing the first armature to be pulled and held, and wherein the second charging current is suitable for causing the second armature to be pulled and held.

4. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to one of the preceding claims, wherein the relay module (100, 200, 300, 400, 500,

600) can be connected to a voltage source (123) which is set up to provide a constant voltage, the first circuit branch (119) and the second circuit branch (121) being connectable to the voltage source (123).

5. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to claims 3 and 4, wherein the first capacitor (1 15) provides the first charging current and the second capacitor (1 17) provides the second charging current when the constant voltage is applied to the first circuit branch (119) and to the second circuit branch (121).

6. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to one of the preceding claims, wherein the first switching state of the switching element (125) has a higher resistance of the switching element (125) compared to the resistance of the switching element (125) in the second switching state and wherein the second switching state of the switching element (125) comprises a lower resistance of the switching element (125) compared to the resistance of the switching element (125) in the first switching state.

7. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to claim 6, wherein the switching element (125) comprises a diode (201), the diode (201) being set up when a forward voltage of the diode ( 201) to transition from the first switching state to the second switching state.

8. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to one of claims 6 or 7, wherein the switching element (125) comprises at least one further diode and / or a series resistor (203).

9. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to one of claims 1 to 6, wherein the switching element (125) comprises a transistor (301), in particular a bipolar transistor or a MOSFET.

10. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to claim 9, wherein the transistor (301) is preceded by an RC element (309) and a voltage divider (303) by which a time constant is defined.

1 1. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to claim 9, wherein the transistor (301) is connected upstream of a controller (401), in particular a microcontroller, which is set up as a function of a measured current in the first circuit branch (1 19) or the second

Circuit branch (121) to determine a switching time of the transistor (301).

12. The electromagnetic relay module (100, 200, 300, 400, 500, 600) according to claim 11, wherein the controller (401) is set up to provide a switching voltage for switching the switching element (125) when the measured current falls below a predetermined limit value.

13. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to one of claims 9 to 12, wherein a first blocking diode (315) between the first relay (103) and the switching element (125) is arranged to one Block current flow from the switching element (125) to the first relay (103) and a second blocking diode (317) is arranged between the second relay (105) and the switching element (125) to allow current flow from the second relay (105) the

Lock switching element (125).

14. Electromagnetic relay module (100, 200, 300, 400, 500, 600) according to one of the preceding claims, wherein the relay module (100, 200, 300, 400, 500, 600) is a safety relay module in order to perform a safety-relevant function and wherein the first relay (103) and the second relay (105) are redundant relays.

15. Arrangement with an electromagnetic relay module (100, 200, 300, 400, 500, 600) according to one of claims 1 to 14 in an emergency stop switch (701) or a protective door switch or a magnetic switch or with a light grid.