Connectors, instrument assemblies and methods of connecting or disconnecting electrical connections under power

A gas sensor assembly for use in an environment in which a combustible gas may be present, comprising:

• a first housing section including a plurality of electrically conductive contacts therein;
• at least one of the contacts of the first housing section being electrical connectible to a power source;
• and
• a second housing section including a plurality of electrically conductive contacts that can form an electrical connection with the contacts of the first housing section, at least one of the contacts of the second housing section being in electrical contact with a gas sensor, the first housing section and the second housing section being removably connectable, the first housing section and the second housing section being capable of forming an explosion proof housing when connected, the contacts of at least one of the second housing section and the first housing section being movable relative to their respective housing section to align the contacts of the second housing and the contacts of the first housing section during connection of the second housing section to the first housing section, electrically conductive connection between the contacts of the first housing section and the contacts of the second housing section occurring during connection of the second housing section to the first housing section in a manner such that when connection between the contacts of the first housing section and the contacts of second housing section occurs, the first housing section and the second housing section are in sufficient connection to form an explosion proof housing.