800w spindle - noise & controlling remotely

[Boyan Silyavski]

Ok, the seller graciously let me off the hook :-) (lesson learnt - never buy when you're tired & don't trust the Ebay search....get into the detail!)

So ok, since I've now I've been won over into getting a VFD for me 800W water cooled spindle ....the Toshiba in Italy is 0.75KW OUTPUT ...& whilst i'll never upgrade the spindle that I have to a larger one, i do agree with jonathan that it's best to over spec (therefore buy a 1.5kw vfd) because the components will be rated higher & won't break out into a sweat. This leads me back to Chinese ....but there seems to be a huge number out there.

Is there any one particular model that I should seek out? (or avoid?!)

Some VFDs seem to be sent from Portsmouth...which appeals as I'd rather not wait 4 weeks to get up & running on my new machine purchase.

Manufacturers state that its Not OK to oversize or under size VFD . The maximum acceptable is 1 size bigger. I believe its because of trip sensitivity. Obviously 4.5 A rated VFD like the 800W can drive 1500w motor. As 800w spindle consumes 2-2.5A in reality and 1500w motor consumes 4A.

So in fact there is no need at all to oversize VFD as they are strong enough for 10 years non stop use as i remember from the specs. You should check though the manual if you decide to oversize. Need to check if you can program all the parameters of your current motor, like current draw, size, etc. cause what is the point of getting bigger if it could not drive properly the motor you have. Cause i believe certain manufacturers will not permit programming of smaller motor.


Also to avoid further mistakes, find the specs of your motor. Check at what voltage and what frequency is driven! The VFD i recommended you drives 3 phase motors up to 400HZ at 230v. Check if your motor is 200, 300, 400hz or even more and if 230 or more volts. This is very important so you can couple it correctly with the VFD.