I've just bought an old Dronsfield Eagle no 2 Surface Grinder, and I need a little bit of help with the electrics (bear with me here, as I'm more than a bit electrically dyslexic). The item was sold as 3-phase, has a Brook 'Gryphon' motor labelled as
3-phase, but only appears to run on 3 wires. Wiring from the motor goes into a standard MEM 15 amp isolator mounted on the machine but has only one red, one blue, and one yellow wire. I've always known the 3-phase machinery we use in the factory to have 3 lives, a neutral, and an earth. Now I know this thing must be around 40 years old, although it's in surprisingly clean and unworn condition, but were 3 phase wiring or motors this different back then? Ultimately I want to run it off single phase in the garage. ThanksPeter