A connection unit connects an electrical supply line to a connection element of a heatable exhaust gas system. The connection unit has a housing having a connection element receiving region extending in the direction of a first housing axis (G.sub.1) and a supply line receiving region extending in the direction of a second housing axis (G.sub.2). The connection element receiving region is open in a first axial connection element receiving region end region for receiving the connection element protruding from an exhaust gas system and is closed off in a second axial connection element receiving region end region. The supply line receiving region is open to the connection element receiving region in a first axial supply line receiving region end region and is open in a second supply line receiving region end region for receiving an electrical supply line.

A planar heating apparatus includes a substrate, first electrodes on the substrate, second electrodes alternately arranged with the first electrodes, an electrode connector connecting end portions of the first or second electrodes to each other and a power connector connected to the electrode connector and to which a power supply is connected. The power connector extends outside of the substrate.

A planar heating apparatus includes a substrate, first electrodes on the substrate, second electrodes alternately arranged with the first electrodes, an electrode connector connecting end portions of the first or second electrodes to each other and a power connector connected to the electrode connector and to which a power supply is connected. The power connector extends outside of the substrate.

A terminal assembly for a heater system includes a plurality of resistive heating elements arranged in multiple power phases includes a plurality of power busbars, a neutral busbar, a phase barrier disposed between each of the plurality of power busbars, and a plurality of interchangeable couplers. Each power busbar corresponds to a power phase of the multiple power phases and is configured to connect a power lead from one of the multiple power phases and a first end of a plurality of resistive heating elements. The resistive heating elements are in electrical communication with the power lead. The neutral busbar is offset longitudinally from the power busbars and configured to receive a second end of the resistive heating elements. The interchangeable couplers are configured to connect at least a subset of the resistive heating elements to at least one power busbar or at least one neutral busbar.

A terminal assembly for a heater system includes a plurality of resistive heating elements arranged in multiple power phases includes a plurality of power busbars, a neutral busbar, a phase barrier disposed between each of the plurality of power busbars, and a plurality of interchangeable couplers. Each power busbar corresponds to a power phase of the multiple power phases and is configured to connect a power lead from one of the multiple power phases and a first end of a plurality of resistive heating elements. The resistive heating elements are in electrical communication with the power lead. The neutral busbar is offset longitudinally from the power busbars and configured to receive a second end of the resistive heating elements. The interchangeable couplers are configured to connect at least a subset of the resistive heating elements to at least one power busbar or at least one neutral busbar.

A current feedthrough for an electrically heatable catalytic converter, which has inside it at least one electrical conductor that can be electrically contacted by the current feedthrough, a central electrically conductive inner conductor, which is guided from the interior of the catalytic converter through the outer housing wall thereof, an electrical insulation layer, which surrounds the electrically conductive inner conductor on the radially outer surface thereof, and a metallic outer tube, in which the electrically conductive inner conductor and the electrical insulation layer are accommodated.

An exhaust gas treatment arrangement for an exhaust gas system of an internal combustion engine includes at least one electrically excitable heating unit having a heating region arranged in an exhaust gas guiding housing such that exhaust gas can flow thereover, and two connection regions passing through the exhaust gas guiding housing for connection to electrical connection lines running outside the exhaust gas guiding housing. A connection line installation aid is fixed with respect to the exhaust gas guiding housing and has at least one connection line positioning recess in an installation aid body for receiving a connection line to be connected to one of the connection regions.

An exhaust gas treatment arrangement for an exhaust gas system of an internal combustion engine includes at least one electrically excitable heating unit having a heating region arranged in an exhaust gas guiding housing such that exhaust gas can flow thereover, and two connection regions passing through the exhaust gas guiding housing for connection to electrical connection lines running outside the exhaust gas guiding housing. A connection line installation aid is fixed with respect to the exhaust gas guiding housing and has at least one connection line positioning recess in an installation aid body for receiving a connection line to be connected to one of the connection regions.

A terminal pin, in particular for a terminal unit for the electrical contacting of a heating conductor of an exhaust-gas heater of an exhaust-gas system of an internal combustion engine, includes a pin body which is elongate in the direction of a pin body longitudinal axis and which has an outer connection region for the connection of a voltage supply line to the terminal pin, a cooling region, a leadthrough region for the electrically insulated leadthrough of the pin body through a pin support of a terminal unit, and an inner connection region for the connection of the terminal pin to a heating conductor of an exhaust-gas heater, a cooling surface formation being provided in the cooling region.

A terminal pin, in particular for a terminal unit for the electrical contacting of a heating conductor of an exhaust-gas heater of an exhaust-gas system of an internal combustion engine, includes a pin body which is elongate in the direction of a pin body longitudinal axis and which has an outer connection region for the connection of a voltage supply line to the terminal pin, a cooling region, a leadthrough region for the electrically insulated leadthrough of the pin body through a pin support of a terminal unit, and an inner connection region for the connection of the terminal pin to a heating conductor of an exhaust-gas heater, a cooling surface formation being provided in the cooling region.