The present disclosure provides a degassing membrane tube module and an online gas-in-oil monitoring apparatus for a vacuum on-load tap changer (OLTC). The online gas-in-oil monitoring apparatus includes an online monitoring housing, an oil inlet tube, a gas monitoring device, an oil tank, and an oil diffusing screen, where one end of the oil inlet tube extends through an inner wall at one side of the online monitoring housing; the gas monitoring device is located on a top inner wall of the online monitoring housing; and a front end of the oil inlet tube is provided with the degassing membrane tube module for online preliminary degassing on insulating oil. With the degassing membrane tube module, the online gas-in-oil monitoring apparatus can increase removal rates for gases in the insulating oil within a short time, and can perform degassing on various gases in the insulating oil.

A switching module is for an on-load tap-changer. The switching module has: a plate having a first side and a second side that is opposite the first side; a vacuum interrupter; and a bridge switch. The vacuum interrupter is on the first side, and the bridge switch, which is directly behind the vacuum interrupter, is on the second side.

A compact vacuum interrupter has an insulator element, a moving contact connection, a fixed contact connection, a moving contact, and a fixed contact. The moving contact has a moving contact rod and a moving-contact contact element. The fixed contact has a fixed contact rod and a fixed-contact contact element. The moving contact is formed with a material that is mechanically stronger than a material of the fixed contact.

A diverter switch is for an on-load tap-changer. The diverter switch includes: at least one vacuum interrupter; an actuating element, which is mechanically connected at a first end of the vacuum interrupter and has a roller at a second end; and an actuating body having a base body and having at least one cam. The vacuum interrupter is configured to be actuated via the actuating element as a result of the roller moving over the actuating body. At least one part of the cam has a higher strength than the base body.

A dropout recloser is capable of in accordance with its operating programming after a predetermined number of fault interrupting operations, e.g., 1, 2, 3 or more but typically 3, to drop out of a cutout and hang freely in a hinge contact of the cutout providing sectionalization with an observable visible gap. The recloser includes fault interrupting and reclosing components, a drop out mechanism and a controller. The drop out mechanism may include a bi-stable actuator to affect fault interrupting operation and dropout operation. The device may include motion limiting structures. The recloser may have a number of operating modes or sequences.

An on-load tap changer of a resistor type includes a selector base plate; a selector mounted on the selector base plate; a diverter switch base plate; a diverter switch mounted on the diverter switch base plate and having a transition resistor; and a common drive shaft which is configured to actuate the selector and the diverter switch.

A switching element for a tap changer, the switching element having a vacuum interrupter that includes a movable contact, a plunger connected with the movable contact, and a housing, in the interior of which, the movable contact is arranged. The switching element also has an actuator configured to actuate the plunger and thereby actuate the movable contact; and a guide. The guide is arranged outside of the housing and is attached to the actuator such that, when actuation of the movable contact takes place, the guide is configured to move therewith. The guide surrounds the housing at least in part, and at least a sub-region of the guide bears against the housing such that, when the movable contact is actuated, the sub-region is moved along the housing.

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.

An on-load tap changer is provided having a plurality of modules, each of which is operable to change taps in a transformer winding. The tap changer includes a motor connected to rotate at least one shaft. The at least one shaft is connected to the tap change modules and is operable upon rotation to cause the tap change modules to each perform a sequence of operations that effectuate a tap change. A multi-turn absolute encoder is connected to the at least one shaft. A monitoring system is connected to the encoder and is operable to determine from the position of the at least one shaft where the tap change modules are in the sequence of operations.

A dropout recloser is capable of in accordance with its operating programming after a predetermined number of fault interrupting operations, e.g., 1, 2, 3 or more but typically 3, to drop out of a cutout and hang freely in a hinge contact of the cutout providing sectionalization with an observable visible gap. The recloser includes fault interrupting and reclosing components, a drop out mechanism and a controller. The drop out mechanism may include a bi-stable actuator to affect fault interrupting operation and dropout operation. The device may include motion limiting structures. The recloser may have a number of operating modes or sequences.