Thor, or should that be Zeus?

**Chaz** · 12-10-2017

Originally Posted by Clive S

Go on Chaz give us a clue

On another note what is the max spindle speed and a link to it would be nice.

Its an HSD ES909. 6.8KW 24K RPM with ISO 30 tool holding. Small issue to actually power it but working on that. It runs happily off 220V, even though its a 380V unit. I cant get to the wiring to Delta the motor (these came as options for both voltages) so I'm hoping that I can run off 220V for now. It has two thermisotors which will trip if it gets too hot. I dont need to cut at 6 KW, even at 2KW im removing a fair bit of material and I now have an tool changer. Buying balanced ISO 30 holders is pricy but will build up a collection once I am happy that this works reliably.

**Chaz** · 16-10-2017

A quick test cut. Looks like Ill be ordering more tool holders. Happy with the initial results. My Z is fairly heavy however (As predicted), might need to look at changing the gearing on both X and Z axis now.

**Chaz** · 16-10-2017

Ah, braking resistors. Even on my 4KW spindle, I keep getting issues where when I stop the spindle, my VFD goes into overvolt trip. Pain in the ass. Anyone have a view on what size resistor I need for the Hyanyang VFD for this spindle?

Thanks

**Clive S** · 16-10-2017

Originally Posted by Chaz

Ah, braking resistors. Even on my 4KW spindle, I keep getting issues where when I stop the spindle, my VFD goes into overvolt trip. Pain in the ass. Anyone have a view on what size resistor I need for the Hyanyang VFD for this spindle?

Thanks

Is there not some setting in the vfd to ramp the speed down say over about 4 secs

**Chaz** · 16-10-2017

Originally Posted by Clive S

Is there not some setting in the vfd to ramp the speed down say over about 4 secs

Ive tried that. All settings, unless I put it on something like a 40 seconds rampdown, it trips.

**m_c** · 16-10-2017

Download a manual for a decent brand of VFD, which actually lists braking resistor sizes, and see what they recommend for a similar sized VFD/Motor combination.

**Chaz** · 16-10-2017

Originally Posted by m_c

Download a manual for a decent brand of VFD, which actually lists braking resistor sizes, and see what they recommend for a similar sized VFD/Motor combination.

Thanks, will try that.

**Chaz** · 16-10-2017

Some research done. Seems the Chinese VFDs dont come with the internal circuitry to use a braking resistor. Will need to clarify that first.

From what I can tell, values are between 30 - 70 Ohm and around 300W.