Methods and devices are provided that allow for easy replacement of a motor assembly in a fuel dispensing unit. In one embodiment, a protective end cap for use with a motor assembly is provided and includes a junction box housing having a sealed end that can couple to a motor, and an opposite open end that can couple to an end plate. The junction box housing can be configured to house a junction box that allows electrical wires extending through the end plate to couple to electrical wires extending from the motor through the sealed end of the junction box housing. A motor assembly having a junction box housing and methods for replacing a motor assembly in a fuel dispenser are also provided.

A housing of a field device of measuring- and automation technology, comprising a housing body, which has at least two housing chambers, wherein the housing chambers are connected together by an opening. The opening is adapted to accommodate a circuit board which is held by at least one holder, wherein the circuit board is adapted to be populated with electronic components or assemblies. The opening is Ex-d sealed with a potting compound.

A housing of a field device of measuring- and automation technology, comprising a housing body, which has at least two housing chambers, wherein the housing chambers are connected together by an opening. The opening is adapted to accommodate a circuit board which is held by at least one holder, wherein the circuit board is adapted to be populated with electronic components or assemblies. The opening is Ex-d sealed with a potting compound.

An explosion-proof apparatus includes a frame having a hollow shape; a gas supply device configured to maintain inside of the frame at pressure higher than certain pressure by supplying gas to the inside; an electrical component disposed inside the frame; a battery configured to supply power to the electrical component; a protective device configured to stop power supply from the battery to the electrical component; a battery housing enclosure being an increased-safety explosion-proof enclosure configured to house the battery therein; and a protective device housing enclosure being a flameproof explosion-proof enclosure configured to house the protective device. The battery does not include a management device that manages parameters of the battery.

An explosion-proof apparatus includes a frame having a hollow shape; a gas supply device configured to maintain inside of the frame at pressure higher than certain pressure by supplying gas to the inside; an electrical component disposed inside the frame; a battery configured to supply power to the electrical component; a protective device configured to stop power supply from the battery to the electrical component; a battery housing enclosure being an increased-safety explosion-proof enclosure configured to house the battery therein; and a protective device housing enclosure being a flameproof explosion-proof enclosure configured to house the protective device. The battery does not include a management device that manages parameters of the battery.

A housing with an inner lining, made of an open-pore material, preferably covering at least two sides of the housing, for the reduction of internal explosion pressure. In addition, or alternatively, a molded body made of the open-pore material, for example a bonded fibrous material, may be arranged in the housing.

A protection system for an electrical machine includes a first connecting line for connecting an internal space of the electric machine to an external space surrounding the electrical machine, a valve, and a filter which is impermeable to dust. The valve and the first connecting line are configured to render the first connecting line impassable when the valve is closed, and to enable a first gaseous medium to enter the internal space from the external space when the valve is open. The filter is configured to filter the first gaseous medium that enters the internal space from the external space through the first connecting line.

A protection system for an electrical machine includes a first connecting line for connecting an internal space of the electric machine to an external space surrounding the electrical machine, a valve, and a filter which is impermeable to dust. The valve and the first connecting line are configured to render the first connecting line impassable when the valve is closed, and to enable a first gaseous medium to enter the internal space from the external space when the valve is open. The filter is configured to filter the first gaseous medium that enters the internal space from the external space through the first connecting line.

A fluid transfer pump assembly that includes a motor enclosure assembly that forms a motor cavity sized to receive a motor. The motor enclosure includes a flame path that extends from an interior joint to an exterior joint. The interior joint faces the motor cavity and the exterior joint faces exterior of the motor enclosure assembly. A heat sink is located in the motor cavity of the motor enclosure assembly. A portion of the heat sink abuts the interior joint.

A protection arrangement of an electric machine which includes a plurality of solid elements layered one after another between a terminal box and a stator of the electric machine. Each of the solid elements includes a cable hole, and the cable holes are arranged to at least partially overlap with each other in order to have a cable channel of the successive cable holes through the solid elements. At least a part of the solid elements are adjustable in a radial direction of the cable channel for making a diameter of the cable channel equal to or smaller than a diameter of the electric cable input in the cable channel in response to adjustment in the radial direction. The protection arrangement comprises a locking mechanism which immobilizes the at least part of solid elements.