I have a Leeson 3/4 HP motor available to me, which I want to turn a pulley on my lathe and control voltage via a Penta KB Power KBWM-120.

I am a little lost on how best to do this or if I have the right combination of devices. I am going AC 110V into the KBWM device, which has two DC outs (L1 and L2). The motor wiring diagram has L1, L2 and L3. What would L3 be in this situation? enter image description here

Also, the motor has settings for 208 or 230v, but my KBWM outputs 0-90V. Would I need to get a 240V controller to run this motor?

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    \$\begingroup\$ The nameplate says it is 1.5 HP and it sure looks like 3-phase AC to me. Especially with that rotation interchange any 2 line leads statement on it. \$\endgroup\$
    – jonk
    Sep 19, 2020 at 2:53
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    \$\begingroup\$ It's a 3 phase motor with wiring configurations (on T1 to T9) shown for 240 or 460V. You need a source of 3 phase (a VFD, unless you have 3-phase suppy to your workshop) and you CANNOT use a DC motor controller. Good motor so get a VFD. \$\endgroup\$
    – user16324
    Sep 19, 2020 at 11:45

1 Answer 1


It's a 3-phase motor, hence L1, L2, L3. Also, more directly, PH: 3

You will need a VFD for that. Your KB controller is for a brushed DC motor.

The good news is that the VFD + 3-phase motor will probably give you much nicer control for your lathe than a DC motor would, including low-end torque for turning larger diameters. Leeson is a good brand of motor.

A VFD (Variable Frequency Drive) in this size range will typically accept 240VAC single phase input and output 3-phase at varying frequency to change the motor speed. Some accept only 3-phase input and some will accept either, but operate with a derated output power when fed with single phase, so take care in the selection.

  • \$\begingroup\$ Ah, many thanks for introducing us a good motor manufacturer in the US, I mean in those were the days. I also know that in those days. Mubushi JP is was a good brand in toy motors. Sadly, in these days, especially in my city, we only know cheap brands from CN. \$\endgroup\$
    – tlfong01
    Sep 19, 2020 at 6:23
  • \$\begingroup\$ @tlfong01 I think Leeson and Bodine are solid US makes. They're probably not in the same class as the Faulhabers and Maxons. For more consumer-ish small applications, Mabuchi is usually okay, no matter where they are made. \$\endgroup\$ Sep 19, 2020 at 6:32
  • \$\begingroup\$ I am pretty sure there are 120V input VFD's available, too. At least there are for 1 HP motors. \$\endgroup\$
    – user57037
    Sep 19, 2020 at 6:45
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    \$\begingroup\$ 120V input VFD's output 240V three phase. The DC link voltage is same as 240V input VFD's. First example I found is this one: Weg CFW300A06P0S1NB20. But I also have a Hitatchi VFD that runs 240 V motors from 120V input. \$\endgroup\$
    – user57037
    Sep 19, 2020 at 6:50
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    \$\begingroup\$ @mkeith Ah, you're right. They must have the doubler circuit. \$\endgroup\$ Sep 19, 2020 at 6:51

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