In article . com,
says...


Other than for underground wiring connections, which are about like a
skinny cigar tube and have clamping screws and silicone gel to
weatherproof them, I don't recall seeing butt connectors rated for
household voltages. All that I have or have seen were for low voltage use.


I have used many of them on 120 volt AC circuits where I worked. They
were rated for 600 volts. Even Lowes has them at thie voltage rating.

https://www.lowes.com/pd/Utilitech-1...t-Splice-Wire-
Connectors/999952958

If it was my vacuum I would probably cut the wires in a staggered
lengths and solder them together and use some heat srink tubing as I
have this equipment in my house.
If only butt splices and tape were around I would use it. However for
those that have to ask, I would go with a new cord.

Guess the main questionfor me is how did the cord get cut in the first
place ?