The selection of the main circuit terminals may seem over the top, in design nothing should be beyond the notice and attention of the designer.
The note in the section 02.09.19.01 entitled starter design – design responsibility where a generator manufacturer supplied inferior components to bolster maintenance contracts, well it was the terminals that were his main money spinner admittedly they were the control terminals and not the main terminals.
The main terminals are the interface point between the starter and the external cables to the motor. These terminals must carry the motor full load and starting currents and the short circuit currents under fault conditions. The external connections will be made on site whereas the internal connections are made in a factory under controlled conditions. The external cable size will not be a constant for a given size of motor as it will change depending on the distance to the motor as the cable size will change to meet the volt drop limitations. Therefore the terminals must be capable of accepting a wide range of cable sizes. It is for this reason that terminals suitable for bolted connections are used throughout the starter range.