Thor, or should that be Zeus?

[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

[Clive S]

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]

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]

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]

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]

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.

[Zeeflyboy]

totally not jealous....

Serious machine you have there Chaz. You must be chuffed!