Arrangement for disconnecting branches of a low voltage supply network under short circuit conditions
AssigneeSiemens Aktiengesellschaft
InventorsFritz Pohl, Wilfried Jaehner
Life of this patent
Estimating the term…
Abstract
A single circuit-breaker is provided in the phase conductor, and the bridging circuit is provided on the load side of the single circuit-breaker, and a magnetically driven switching contact closes a bridging current branch leading to the neutral conductor. The bridging circuit conducts a part of the short-circuit current past the magnetic drive and/or the switching contact. A resistor whose resistance value amounts to between 25 and 50% of the value of the smallest load-circuit impedance (L.sub.2, R.sub.2) to be expected, may be provided in the bridging current branch. In such an arrangement, the bridging circuit and the circuit-breaker can form one unit.
Claims12
An apparatus for disconnecting branches of a low voltage supply network under short circuit conditions, wherein consumers are coupled in one branch to a phase conductor and to a corresponding neutral conductor, the apparatus comprising:
- a switching element coupled in an incoming circuit to the consumer in order to switch the switching element to at least one of an on state and an off state;
- a single circuit-breaker disposed in the phase conductor;
- and
- a bridging circuit positioned on a load side of the single circuit-breaker and disposed in at least one of the phase conductor and the neutral conductor, the bridging circuit including a first magnetic drive and a bridging switch, the bridging switch having a magnetically driven switching contact for closing a bridging current branch leading to the neutral conductor, the bridging current branch including a resistor having a resistance value between 25% and 50% of a value of a smallest expected load-circuit impedance,
- wherein the bridging current branch conducts a part of a short-circuiting current through the magnetically driven switching contact in the bridging circuit so that the magnetically driven switching contact leading to the neutral conductor is closed.
An apparatus for disconnecting branches of a low voltage supply network under short circuit conditions, wherein consumers are coupled in one branch to a phase conductor and to a corresponding neutral conductor, the apparatus comprising:
- a switching element coupled in an incoming circuit to the consumer in order to switch the switching element to at least one of an on state and an off state;
- a single circuit-breaker disposed in the phase conductor;
- and
- a bridging circuit positioned on a load side of the single circuit-breaker and disposed in at least one of the phase conductor and the neutral conductor, the bridging circuit including a first magnetic drive and a bridging switch, the bridging switch having a magnetically driven switching contact for closing a bridging current branch leading to the neutral conductor, the bridging current branch including a resistor having a resistance value between 25% and 50% of a value of a smallest expected load-circuit impedance,
- wherein the bridging current branch conducts a part of a short-circuiting current through the magnetically driven switching contact in the bridging circuit so that the magnetically driven switching contact leading to the neutral conductor is closed, and
- wherein the circuit-breaker and the bridging circuit form one unit.
An apparatus for disconnecting branches of a low voltage supply network under short circuit conditions, wherein consumers are coupled in one branch to a phase conductor and to a corresponding neutral conductor, the apparatus comprising:
- a switching element coupled in an incoming circuit to the consumer in order to switch the switching element to at least one of an on state and an off state;
- a single circuit-breaker disposed in the phase conductor;
- a bridging circuit positioned on a load side of the single circuit-breaker and disposed in at least one of the phase conductor and the neutral conductor, the bridging circuit including a first magnetic drive and a bridging switch, the bridging switch having a magnetically driven switching contact for closing a bridging current branch leading to the neutral conductor, the bridging current branch includes a resistor having a resistance value between 25% and 50% of a value of a smallest expected load-circuit impedance;
- and
- a thermal trip element for the circuit-breaker, the thermal trip element being disposed on the load side of the bridging current branch,
- wherein the bridging current branch conducts a part of a short-circuiting current through the magnetically driven switching contact in the bridging circuit so that the magnetically driven switching contact leading to the neutral conductor is closed.
An apparatus for disconnecting branches of a low voltage supply network under short circuit conditions, wherein consumers are coupled in one branch to a phase conductor and to a corresponding neutral conductor, the apparatus comprising:
- a switching element coupled in an incoming circuit to the consumer in order to switch the switching element to at least one of an on state and an off state;
- a single circuit-breaker disposed in the phase conductor;
- and
- a bridging circuit positioned on a load side of the single circuit-breaker and being disposed in at least one of the phase conductor and the neutral conductor, the bridging circuit including a first magnetic drive and a bridging switch, the bridging switch having a magnetically driven switching contact for closing a bridging current branch leading to the neutral conductor, the bridging current branch including a resistor having a resistance value between 25% and 50% of a value of a smallest expected load-circuit impedance,
- wherein the bridging current branch conducts a part of a short-circuiting current through the magnetically driven switching contact in the bridging circuit so that the magnetically driven switching contact leading to the neutral conductor is closed, and
- wherein the switching contact of the magnetically driven switch of the bridge circuit is made of weld-resistant contact materials.
A multipole bridging apparatus for multi-phase networks under short circuit conditions, wherein consumers are coupled in the branch to a phase conductor and to a corresponding neutral conductor, the multipole bridging apparatus comprising:
- a switching element coupled in an incoming circuit to the consumer in order to switch the switching element to at least one of an on state and an off state;
- a single multipole circuit-breaker disposed in the phase conductor;
- and
- a bridging circuit positioned on a load side of the single circuit-breaker and being disposed in at least one of the phase conductor and the neutral conductor, the bridging circuit including a first magnetic drive and a bridging switch, the bridging switch having a magnetically driven switching contact for closing a bridging current branch leading to the neutral conductor, the bridging current branch including a resistor having a resistance value between 25% and 50% of a value of a smallest expected load-circuit impedance
- wherein the bridging current branch conducts a part of a short-circuiting current through the magnetically driven switching contact in the bridging circuit so that the magnetically driven switching contact leading to at least one of a common point of the bridging current branch and the neutral conductor is closed.
Dependencies are inferred from the claim text.