Device for measuring a condition of an electric switch, electric switch and method for measuring a condition of an electric switch

1. An apparatus for measuring a state of an electrical switch, the apparatus comprising:

a first high voltage (HV) line comprising a first contact, a second HV line comprising a second contact, and at least one high-impedance resistor, wherein the resistor is configured to interrupt a flow of current on one of the HV lines,

wherein the apparatus is located inside a housing of the electrical switch, and

wherein the apparatus is configured to tap a voltage at outer main contacts of the electrical switch located inside the housing.

2. The apparatus according to claim 1 , wherein the resistor has a value configured to permit a maximum flow of current of 1 mA in case of an external short-circuit of the first and second HV lines.

3. The apparatus according to claim 1 , wherein the first contact and the second contact are configured to be connected directly to the outer main contacts of the electrical switch.

4. The apparatus according to claim 1 , further comprising a carrier, wherein the first contact, the second contact and the resistor are arranged on the carrier.

5. The apparatus according to claim 1 , wherein the at least one high-impedance resistor comprises at least one first high-impedance resistor and at least one second high-impedance resistor, wherein the respective resistor is configured to interrupt the flow of current on the respective HV line.

6. An electrical switch comprising:

an apparatus comprising a first high voltage (HV) line comprising a first contact, a second HV line comprising a second contact, and at least two high-impedance resistors;

a first outer main contact;

a second outer main contact; and

a housing,

wherein the first contact is directly connected to the first outer main contact and the second contact is directly connected to the second outer main contact,

wherein the apparatus is integrated into the electrical switch and configured to:

tap a voltage at the first and second outer main contacts inside the housing of the electrical switch, and

measure a state of the electrical switch.

7. The electrical switch according to claim 6 , wherein the resistors are arranged inside the housing.

8. The electrical switch according to claim 6 , wherein two resistors are provided for each main contact.

9. The electrical switch according to claim 6 , wherein the first contact and the second contact are sliding contacts.

10. The electrical switch according to claim 6 , wherein the first contact and the second contact are fixedly connected to their respective outer main contact.

11. The electrical switch according to claim 10 , wherein the first contact and the second contact are welded or soldered to their respective outer main contact.

12. A method for measuring a state of an electrical switch, the method comprising:

providing the electrical switch having a first outer main contact and a second outer main contact;

providing a housing;

providing an apparatus for tapping a voltage at the first outer main contact and the second outer main contact, wherein the apparatus is integrated into the electrical switch inside the housing, and wherein the apparatus has a first contact, a second contact, at least two high-impedance resistors, a first high voltage (HV) line and a second HV line;

directly connecting the first contact to the first outer main contact;

directly connecting the second contact to the second outer main contact; and

linking the HV lines to an A/D converter.

13. The method according to claim 12 , wherein the first and second contacts are welded or soldered to the first and second outer main contacts.

14. The method according to claim 12 , wherein the apparatus further comprises a carrier, and wherein the carrier is placed onto the electrical switch for direct connection between the first and second contacts and the first and second outer main contacts.

15. The method according to claim 12 , wherein the apparatus is arranged at least partly inside the housing.