Myford 3 phase motor upgrade

[Howard LewisParticipant @howardlewis46836]

Even with three phase supply, vibration can still be evident. It may be caused mechanically rather than electrically.

My oriental lathe, replacing a ML7, (to get a Norton box, and a big bore mandrel) was fitted with VFD prior to delivery, and is very satisfactory. The pendant looks like one of the commercially available ones.

From the safety aspect, a microswitch will break the 24volt supply to the contactor if any of the covers to Gears , Belt, or Chuck Guard are opened..

The original twelve speeds, became six (single sheave pulley on the three phase motor because of space considerations, in place of the two sheave on the original single phase unit), but with variable speed on each range.

However, at maximum speed, (higher than standard, since the invertor allows the motor to be run up on 60Hz rather than to UK and European standard mains frequency of 50Hz), some vibration is evident. This is ascribed to the Bull Wheel being unbalanced by the pin used to lock the bull wheel to the shaft).

I always slacken the secondary (Countershaft to Mandrel) belt when not in use, so unlikely to be the V belt taking a set.

Howard

[Brian AbbottParticipant @brianabbott67793]

Just a quick Thankyou for all your advice.

Got a unit from transwave in the end, cheap as chips in comparison to others, piece of cake to fit and program so pleased as punch with it..

Used a metric motor and just made a simple fixing plate..

Still have a knock from somewhere..need to investigate but that's another story.

thanks again

[Harry WilkesParticipant @harrywilkes58467]

Just wondering for those members that have gone the DIY route and fitted a 'metric' motor what frame/size did you go for ?

Cheers H

[Brian AbbottParticipant @brianabbott67793]

It was an 80 frame motor..

Simple plate added to allow fitting and a new pulley..

[Harry WilkesParticipant @harrywilkes58467]

Posted by Brian Abbott on 21/10/2014 13:25:38:

It was an 80 frame motor..

Simple plate added to allow fitting and a new pulley..

Many thanks

H

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