Vfd For A Bridgeport

Always check the factory manuals for compatability.

Our Allen bradley manual has a table with motor size, single pase and 3 phase power ratings and the vfd required for each.

Many vfd can operate from single phase with derating as the input side is on one set while others simply should not be used.

Our BP has 1 hp motor and po had 3 phase and used 1 hp unit and we have issues when we push it.

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I would also suggest going with a 2Hp VFD, evidently the BP pancake motors can be a bit difficult to drive from my readings. Also, some of the mill motors I have seen are 2 speed 4P/8P constant Hp, on the 8P setting they use twice the current so one would need to up size the VFD if it was run on 8P winding. You also may try the VFD without an external braking resistor, there is a built in internal braking resistor and it should be good for stopping the mill in 2-3 seconds.
 
OK, good to know. My motor is definitely single speed, 240/480 star wound. Was considering going 1.5 HP on the VFD.
 
Update.
I went with the Lenze 1.5 Hp VFD. My motor is rated @ 4.2 amp with a 1.25 duty cycle, the 1.5 Hp VFD is good for 6 amps so I've got some headroom. Just finished installing and programing. This thing is flat out cool! I used the existing drum switch for control inputs and added a speed pot. The third step down on the pullys is unity between motor & spindle and with frequencies set from 20 to 95 hz I can get full range of spindle speeds without moving the belt. The other nice thing is that you can set the VFD to display RPM directly. I think my lathe needs one of these!
 
Update.
I went with the Lenze 1.5 Hp VFD. My motor is rated @ 4.2 amp with a 1.25 duty cycle, the 1.5 Hp VFD is good for 6 amps so I've got some headroom. Just finished installing and programing. This thing is flat out cool! I used the existing drum switch for control inputs and added a speed pot. The third step down on the pullys is unity between motor & spindle and with frequencies set from 20 to 95 hz I can get full range of spindle speeds without moving the belt. The other nice thing is that you can set the VFD to display RPM directly. I think my lathe needs one of these!



Oh cool ! Can you give me the parameters you used to compare? I am feeling a bit overwhelmed read this stuff because of all of the settings available.
 
I can, it'll be a little later tonight.
 
OK, here we go:
P100 -1 enables external controls
P102 -20 Min hertz, With belt on second from bottom pully this will give you data plate min. spindle speed.
P103 -95 Max hertz, this will give you max data plate spindle speed.
P104 -3 Acceleration, seconds to 60hz speed.
P105 -5 Deceleration, probably will change this to 7 or 8 as I get a High volt fault when decelerating in back gear.
P108 -70
P111 -1
P112 -1
P121 -10 Enable reverse on terminal 13a
P178 - 29.17 makes display show motor RPM which with belt on step 3 is spindle RPM, cool!!!
P300 -4 enable vector mode
P302 -220 From motor name plate.
P303 -4.2 "
P399 -1 To run SV calibration.

I have the pancake motor circa 1957 and am using the origional drum switch for VFD signaling and a 10K ohm pot for speed. If you are using push buttons the P121 settings are a little different. The manual shows this.
Hope this helps.

Mark
 
Here is a pretty good video of connection and programing.
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OK, here we go:
P100 -1 enables external controls
P102 -20 Min hertz, With belt on second from bottom pully this will give you data plate min. spindle speed.
P103 -95 Max hertz, this will give you max data plate spindle speed.
P104 -3 Acceleration, seconds to 60hz speed.
P105 -5 Deceleration, probably will change this to 7 or 8 as I get a High volt fault when decelerating in back gear.
P108 -70
P111 -1
P112 -1
P121 -10 Enable reverse on terminal 13a
P178 - 29.17 makes display show motor RPM which with belt on step 3 is spindle RPM, cool!!!
P300 -4 enable vector mode
P302 -220 From motor name plate.
P303 -4.2 "
P399 -1 To run SV calibration.

I have the pancake motor circa 1957 and am using the origional drum switch for VFD signaling and a 10K ohm pot for speed. If you are using push buttons the P121 settings are a little different. The manual shows this.
Hope this helps.

Mark


Wow thank you! This will help me tremendously because I have no idea what or what not to select and program.
I actually have that video up on another browser tab. It got me to the point the VFD was running, but its for an older model etc...

What are these for ?

P300 -4 enable vector mode
P302 -220 From motor name plate.
P303 -4.2 "
P399 -1 To run SV calibration.
 
-The P30x parameters are for senserless vector mode. P300 -4 enables the mode we want for our machine tools. P302 thru P306 require motor parameters to be entered for this mode to work, you get these from the motor data plate. I see that your's is a 2Hp so the numbers will be different than mine. P306 is the only one I could not get data for so I left it at default and that seams to work. Perhaps one of the motor gurus here can help with that. You don't need to do this to use the drive as it defaults to voltage/hz mode. However, I spent the extra money to get sensorless vector capability and want to use it. It will run the motor a full torque at reduced speed. Say you are running at 20hz to get a 580 RPM spindle speed because your using a big honking 4 cutter face mill, your going to want full torque like you'd get running the motor at rated speed on pulley step one. 'Course, if you do this a lot, you'll need to add a cooling fan to the motor because at 580 RPM it's built in fan won't move enough air. I saw your other post on this and if the motor runs backwards, and mine did, just swap any two line connections at the motor, same as any 3 phase motor.
 
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