An on-load tap changer has: a first selector rod and a second selector rod; a load changeover-switch rod; a switch; and a transmission. The first selector rod, the second selector rod and the load changeover-switch rod are arranged collinearly. The transmission is configured to: move the first selector rod and the second selector rod during changeover from one selector contact to an adjacent selector contact in a first direction; and move the load changeover-switch rod during the changeover in the first direction and a second direction, which is opposite to the first direction, so as to actuate the switch.

A system for determining when an electrical contact or other component reaches a predetermined temperature. In operation, a trace material is dispersed into a surrounding environment (e.g., head space within a compartment above insulating oil), where the trace material is detected. A barrier may be ruptured or broken by temperature-induced gas pressure, or pierced by a spring-loaded member that is located within the same section that contains the trace material, and devices may be provided for moving the trace material through the foil barrier as the barrier is ruptured. The barrier may be opened solely by internal gas pressure. According to another embodiment, improved fail-safe operation may be achieved by providing a spring-loaded member and configuring the barrier to be ruptured by the pressure of the detectable gas material before the barrier is ruptured by the spring-loaded member.

A switch includes a diverter contact; a primary fixed contact; and a secondary fixed contact. The switch additionally includes a primary movable contact configured to be pivoted, relative to the diverter contact and the primary fixed contact, about a pivot axis between a first end position and a second end position. In the first end position, the primary movable contact bears by a first contact point against the diverter contact and by a second contact point against the primary fixed contact. The switch further includes a secondary movable contact configured to be pivoted, relative to the diverter contact and the secondary fixed contact, about the pivot axis between a first end position and a second end position. In the first end position the secondary movable contact bears by a third contact point against the diverter contact and by a fourth contact point against the secondary fixed contact.

A selector for an on-load tap changer with a diverter switch includes: an insulating plate with a first side and a second side, the second side opposite the first side; a plurality of fixed contacts, which extend from the first side through the insulating plate to the second side; a first movable contact on the first side; a second movable contact on the second side; a first connection, which is connected with the first movable contact and which is connectable with a first branch of the diverter switch; and a second connection, which is connected with the second movable contact and which is connectable with a second branch of the diverter switch. Each of the first moveable contact and the second movable contact are selectably connectable with each of the fixed contacts.

An on-load tap-changer uninterruptedly switches between winding taps of a tap-changing transformer. The on-load tap-changer has: a diverter switch that switches over from a first to a second fixed contact; and a selector that powerlessly preselects the fixed contacts and has a first and second selector arm that are actuated independently and contact each of the fixed contacts. The diverter switch has: a main path with a mechanical switching element that connects the first selector arm to a load take-off lead; a first auxiliary path with a first semiconductor switching element that is parallel to the main path and connects the first selector arm to the load take-off lead, and a second auxiliary path with a second semiconductor switching element that connect the second selector arm to the load take-off lead.

An on-load tap-changer provides uninterrupted diverter switch operation between different winding taps of a tap-changing transformer. The on-load tap-changer includes: a flange module; and a union nut. The on-load tap-changer is configured to be fastened to the tap-changing transformer by the union nut and the flange module.

An on-load tap changing apparatus includes a first switching unit connected to a first tap of a transformer provided in a power system and switching power supplied from the first tap, a first impedance changing unit connected in series with the first switching unit and increasing an impedance when the first switching unit executes a switching operation, a second switching unit connected to a second tap of the transformer and switching power supplied from the second tap, and a second impedance changing unit connected in series with the second switching unit and increasing an impedance when the second switching unit executes a switching operation. The on-load tap changing apparatus can suppress an arc at the time of switching, reduce deterioration of a switching unit, and have excellent durability.

In a method for cleaning an on-load tap changer (19) in a regulating transformer (20), provision is made for the on-load tap changer (19) to comprise a moving contact (11) and a fixed contact (12); for a cleaning signal to be generated; for the moving contact (11) to be frictionally moved relative to the fixed contact (12) on the basis of the cleaning signal. An on-load tap changer (19) in a regulating transformer (20) comprises: a moving contact (11) and a fixed contact (12); a contact drive (17) which is coupled to the moving contact (11); a control device (18) which is connected to the contact drive (17) and is designed in such a manner that the control device can generate a cleaning signal and can transmit said signal to the contact drive (17); wherein the contact drive (17) is designed in such a manner that the contact drive can frictionally move the moving contact (11) relative to the fixed contact (12) on the basis of the cleaning signal.

A switch can be used for an on-load tap changer. The switch includes: fixed contacts, including a first fixed contact and a second fixed contact; and a moving contact with a first attraction element. The moving contact is movable from a first position into a second position via the first attraction element and a second attraction element, which is arranged outside the switch. The moving contact is configured such that, in the first position, the moving contact contacts neither or only one of the fixed contacts and, in the second position, the moving contact contacts both of the fixed contacts.

A system for determining when an electrical contact or other component reaches a predetermined temperature. In operation, a trace material is dispersed into a surrounding environment (e.g., head space within a compartment above insulating oil), where the trace material is detected. A barrier may be ruptured or broken by temperature-induced gas pressure, or pierced by a spring-loaded member that is located within the same section that contains the trace material, and devices may be provided for moving the trace material through the foil barrier as the barrier is ruptured. The barrier may be opened solely by internal gas pressure. According to another embodiment, improved fail-safe operation may be achieved by providing a spring-loaded member and configuring the barrier to be ruptured by the pressure of the detectable gas material before the barrier is ruptured by the spring-loaded member.