Plug-in summation current transformer module, rail-mounted device, and assembly method

A plug-in summation current transformer module for insertion into a module-overlapping installation space of a multi-pole rail-mounted device formed from a plurality of housing modules, the current transformer module comprising:

• a tubular summation current transformer;
• at least one first primary conductor and at least one second primary conductor, each being routed through said tubular summation current transformer and each having a first primary conductor end and a second primary conductor end;
• a primary conductor holder for fixing said first and second primary conductor ends, said primary conductor holder being fastened to said summation current transformer and being configured to adopt a fixing position and a releasing position, said primary conductor holder being configured,
• in the fixing position, to hold said first and second primary conductor ends in a respective assembling position during an insertion into the module-overlapping installation space;
• and
• after insertion, by moving to the releasing position, to bring said first and second primary conductor ends into a respective joining position.