Options for powering 3 phase RAS with DC brake

[Guineafowl]

I’ll soon be moving to somewhere without 3 phase, so I’m looking at options for my Wadkin BRA 350 radial arm saw with Crompton DC brake, much like the one pictured.

- I like the brake - it’s a good addition to a climb-cutting monster.

- Motor is custom to the machine, so single phase swap unlikely.

- I’ve been inside the motor and dug out the star point, so 240V delta is an option.

It’s 3hp with a fast spin-up, but a light blade, so maybe a 4hp static phase converter? How would it cope with the brake?
Add an idler motor to make it into an RPC?
VFD? I’d not have the Crompton brake, and adding a braking resistor looks expensive. Also, there’s a 3ph 2hp Wadkin planer to power.

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[Pete.]

How about a 415v output video and hook the dc brake into a timer relay triggered by the output on the vfd. When the run command is removed the relay closes and do brake applied for however many seconds you specify.

 

[Agroshield]

When the run command is removed the relay closes and dc brake applied for however many seconds you specify.

I wonder if it would also need a relay between VFD and motor. If you apply DC to the motor, it will find its way up the wires and into the VFD. I do not know if that is acceptable from the VFD's point of view or if it will be unhappy. How sensitive are the electronics in the VFD to being back fed with DC?

In its normal configuration, when plugged into a mains 415v supply, I would guess that the machine isolates itself from the mains (contactor opens) before the DC is sent in.

 

[Guineafowl]

I’m not sure what voltage the DC brake applies, but it might drive current back to the VFD via the freewheel diodes embedded in the output transistors.

 

[iNf]

Would it be easier (depending on cost) to have a rotary converter, that way you could run all your current and future 3 phase stuff as is.