Electrical Motor Questions.

I would go the VFD/3-phase motor route (using the motor mentioned below), and fit a no-volt release to the VFD.

If you don't properly tighten the chick, and/or if you try cutting metal when in reverse, it will come off no problem at all.

However, with the VFDs there is usually a soft start feature so the motor cannot be slammed from fast forward to fast reverse, so if you tighten the chuck properly there is no problem.

Rubber mounts.

I hace a very similar setup on my ML7 - works just fine and I don't have a TV in my workshop anyway

If I was doing it again I would probably go for a larger motor than the 1/2 horse motor I have, but for most purposes it is OK as is.

The VFD that I have was supplied by the Newton-Tesla guys (they advertise in MEW and ME from time to time) - I got them to increase the max speed to more than double the motor RPM - the VFD kicks out

120 Hz 3-phase at max speed, so the motor spins at 2.4 times its nameplate RPM at top whack. This means that I very rarely have to change the belt position on the pulleys - I get from dead slow to max speed (in forward or reverse!) just on the VFD controls.

You can get mains RFI filters that are wired between the VFD and the mains supply that will stop the VFD from injecting nasties back down the mains - this should fix the problem if there is one.

Regards, Tony

No need as the VFD if programmed correctly won't restart from a mains failure. The VFD will also act as overload.

That's the nice thing with a VFD it replaces all those weird pressed steel and burnt electrical smelly bits.

-- Regards,

John Stevenson Nottingham, England.

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Hmm Interesting! How does one go about tightening a chick? hehe..

Wayne...

You mean you haven't found out yet?? You don't know what you're missing

Regards, Tony

Yep - brain fade there. Thinking about it, the Newton-Tesla setup doesn't have a NVR but it does have one of those big red STOP buttons that kills the power to the VFD & needs two twists to the left, one to the right, and a sprinkling of Eye of Newt to turn it back on. Probably a smart move to have one of them fitted.

Spoils all the fun though

Regards, Tony

Thanks for the reply gents... Seems like VSD 3 phase motor is the best idea. Now.. Anyone want to buy a Gryphon (0.5hp) 370W Brook Crompton motor, only ever seen 2 hours use in its life - looks like new. It has capacitor start with internal centifugal switch.

Using a bush I guess :-)

No but I do have a vacancy for a 1/2 hp 3ph Cub - the smoke escaped...

ttfn

Can't you buy some new smoke?

Anyone know what usually fails on inverters, ie is there a pattern? Are they ever worth repairing (in 'home shop' sizes)?

Cheers Tim

Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service

escaped...

At a guess, probabilites are o/p switching mosfets, main reservoir capacitors and input resctifer. If the boards are fried then probably not worth the trouble.

AWEM

You won't regret it. I put a Telemecanique ATV11 (cheap + easy to set up) and 3 phase motor on my ML7 a few weeks back and my only regret is not doing it years ago.