Application for a VFD (Lathe Saddle)

[joel89]

Hi,

just wanting to put a VFD on a lathe rapid traverse saddle, anyhow ever done this and does it work ok? it is a poreba lathe 12metre bed 1.1kw 3ph induction motor.

 

[Darkwood]

Any reason why you want to fit a VSD - they tend to fuction fine at full speed with manual for finer set-up, would seem an expensive exercise against a DOL contactor.

 

[joel89]

the reason is to get a nice ramp up, our operators keep shearing the motor shaft i think they are FWD/REV really quickly on selector switch it always happens on nights but cannot prove it, the other thing they do is pull the steady with the saddle, which isnt right but again its the same old argument "Weve always done it like this" so im thinking an inverter will cure the problem I already have a 1.1kw Altivar 312 so cost isnt an issue

 

[Darkwood]

Cheaper to fit a delay timer and check the motors are not been fitted incorrectly in that the bolts are been tightened in the correct sequence when mounting.

I would also check if there is any play on the gearing by turning the impellor and making sure it doesn't travel before engaging due to mechanical wear, I would suggest you need to find the cause first, a VSD may stop it but its only masking an issue that may cost more in the long run if ignored.