PH1ComptonMotorI have a single phase single volt (UK 220-240) 1Hp electric motor with two capacitors, start and run. As photographed. This is to run my Milling machine. I need to connect the motor, via appropriate switch gear, to mains AC. I appreciate the earth wire connects to the "seventh" terminal at the side. But I have no idea where the Live and Neutral wires need to connect.

I appreciate that the metal strips (as photographed, shown between U1/W2 and V1/U2) manage the rotation, and presently are connected for forward/clockwise rotation, and can be changed to U1/V1 and W2/U2 for reverse/counter-clockwise rotation (which I will probably use). But for either scenario (CW or CCW), to which of the terminals should the Live and Neutral AC wires be connected?

If someone could offer a clear answer please - in terms of U1 etc as per photograph - as I've scoured the internet and have fried my brain looking at too many conflicting options (mostly involving 3phase despite specific search criteria).


1 Answer 1


It goes to U1 and U2 as depicted, on those contacts which have bars on them, Red and Black wire.

  • \$\begingroup\$ Note that pre-EU (i.e. up to early 1970s) UK wiring, RED was LIVE and BLACK was NEUTRAL. In other words this motor appears to follow that convention (though in the photos it looks newer). These connections (to U1,U2 regardless of the metal bar orientation) are marked "SUPPLY" on the label. I feel this is worth mentioning since in the US, BLACK is LIVE which is wrong for this motor. So, LIVE to U1, NEUTRAL to U2. \$\endgroup\$
    – user16324
    Sep 21, 2019 at 12:29
  • \$\begingroup\$ That's great, many thanks. All working ok. \$\endgroup\$
    – user232501
    Sep 23, 2019 at 9:47

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