Could you please tell me the name of the red wire connector/terminal shown in the picture?
That's an insulated bootlace crimp ferrule.
- Insultated so that there is no touch danger when fully inserted into the terminal block. The insulation covers the funnel which guides the strands into the tubular section.
- Bootlace because it's similar to those used to stop boot laces from fraying.
- Crimp because a crimping tool is used to clinch the wires.
- Ferrule /ˈfɛruːl,ˈfɛr(ə)l/ noun a ring or cap, typically a metal one, which strengthens the end of a handle, stick, or tube and prevents it from splitting or wearing.
The colour should indicate the gauge wire it matches.
Image source: Google image search random image.
It's a wire ferrule.
'An electric wire ferrule (sometimes electric end terminal) is a metal tube crimped over stranded wire to secure the strands within a screw terminal. Electrical insulation may be included to protect any exposed portion of the wire not completely inside the screw terminal post. Stranded wire is preferred for most electrical applications because it is more reliable than solid wire. It is more flexible and durable because repeated bending will not cause it to break. Stranded wire can be more difficult to terminate, because the individual strands tend to separate after insulation is removed. By placing the end of the stranded wire in a ferrule, the strands stay together'.
Courtesy - Wikipedia.