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Finished Plugins for Download / Re: Huanyang VFD controller plugin
« on: April 09, 2011, 11:26:55 AM »...
The braking does work but not as I expected it to.
I have a Danfoss VFD on my Bridgeport and with the brake resistor enabled it improves the deceleration considerably from the moment it starts slowing down.
With the brake resistor enabled on the Huanyang and the deceleration time set to the minimum 0.1sec (calculated from 50Hz I think) the slow down rate is not a whole lot different to NOT having it enabled.
The resistor is not used to dump energy until the bus voltage exceeds the max of about 375VDC (don't quote me on that but it's close) which is in the last 10% or so of wind down.
The deceleration time from 24000 rpm (400hz) with a 6mm end mill in the collet is around 5 seconds. Nothing like the setting of 0.8 seconds that the setting implies.
So with the deceleration set to 0.1sec and the resistor NOT plugged in, the VFD lets go of the spindle (coast stop) when the bus voltage gets too high in that last 10%.
With the resistor plugged in you do get an increased deceleration over normal but only in that last 10% and only till the bus voltage drops below the maximum again.
In summary,
I think that my 2.2kw high speed spindle does not have enough inertia to make any use of the breaking function with an external resistor attached.
You can reduce the deceleration time and get some improvement of deceleration without a resistor. If you drop it too much and the bus voltage goes too high the VFD will just disconnect from the spindle until the bus voltage drops again. (as it should)
If I used the Huanyang on the Bridgeport with it's increased inertia it may work as expected, but that is 380V 3 phase and the Huanyang is only 240V rated.
Cheers,
Phil
Hi.
Good work w/ the implementing of the breaking resistor!!
So you mean that I could set my deceleration time to the lowest (0.1) even w/o the resistor and the VFD will be ok w/ it? I don't know what I use today but stop time from 24000rpm is like 12 sec or more.
Any one know what would be a safe acceleration time for the Huanyang VFD w/ 2.2 kw water cooled spindle?
Best regards L.