need electricians help

[Finnster]

Honestly, I would get a whole new power cord/mains and just replace the old wire they have running out, assuming its not intended to be hardwired. (which it seems it is)

Take off the strain relief plug, open up any access panels as needed and remove the old wire and install the new. You don't want to be doing soldering/heatshrinking/electrical tape jobs with equipment like that. Its not safe, and no way its code. You don't want to ever have a situation where there could be a short and you burn down the shop or something for the sake of a cheap power cord.

Be sure to record the wiring pattern before you remove it. I would guess its:

Red=hot
Blue=neutral
yellow=ground

Just a complete guess tho.