01-16-2015, 09:32 PM
Well a 3hp 3phase motor sort of fell into my lap. Was in the rewind shop to get a fan blade for the mule and asked about used motors.
He has a 3 hp 3phase Yaskawa vfd rated motor thats been sitting there forever. As far as he knows it new. Will sell it to me for $100.
The reason its been sitting is its 6 pole. 1160 rpm at 60 hz.
Should have written down more off the tag, got the model (FEK-I) and thought I'd find out what I needed off the net but can't find anything. Think its old, Yaskawa motors are now made by Marathon.
As with most of my creations I like to base them on something that actually was supposed to work. In this case its a VB36 bowl turning lathe.
Though they don't say Im assuming they use a 4 pole motor at 1800 rpm. It has a vfd with 3 belt reduction ranges. 4:! 1.25:1 and 1:1.5 to give a speed range of 50 - 2600 rpm at the spindle.
So on the slowest speed they're operating the motor at 200rpm.
With a 6 pole motor would it be wise to run it at 133 rpm and a 2.6:1 ratio to get the low speed of 50 rpm. Just dividing they're ratio by 1.5 to match the motor speed which should have 1.5 times the torque.
I'd set my ratios at 2.6:1 1:1 and 1:2.6 which would keep the two sets of pulleys the same and the belt at the same length over the range.
He has a 3 hp 3phase Yaskawa vfd rated motor thats been sitting there forever. As far as he knows it new. Will sell it to me for $100.
The reason its been sitting is its 6 pole. 1160 rpm at 60 hz.
Should have written down more off the tag, got the model (FEK-I) and thought I'd find out what I needed off the net but can't find anything. Think its old, Yaskawa motors are now made by Marathon.
As with most of my creations I like to base them on something that actually was supposed to work. In this case its a VB36 bowl turning lathe.
Though they don't say Im assuming they use a 4 pole motor at 1800 rpm. It has a vfd with 3 belt reduction ranges. 4:! 1.25:1 and 1:1.5 to give a speed range of 50 - 2600 rpm at the spindle.
So on the slowest speed they're operating the motor at 200rpm.
With a 6 pole motor would it be wise to run it at 133 rpm and a 2.6:1 ratio to get the low speed of 50 rpm. Just dividing they're ratio by 1.5 to match the motor speed which should have 1.5 times the torque.
I'd set my ratios at 2.6:1 1:1 and 1:2.6 which would keep the two sets of pulleys the same and the belt at the same length over the range.
Free advice is worth exactly what you payed for it.
Greg
Greg