VFD recommendation needed ! Bridgeport Boss Acorn conversion

[RaptorMachine]

Hey Guys,

finally got the machine cleaned up.. repaired the oiling system and ready to start setting up the acorn and related control setup

what is the best VFD i can use with the acorn. the spindle motor is 2 hp


thanks !
Joe

[martyscncgarage]

Hey Guys,

finally got the machine cleaned up.. repaired the oiling system and ready to start setting up the acorn and related control setup

what is the best VFD i can use with the acorn. the spindle motor is 2 hp


thanks !
Joe

Can't go wrong with GS2 or GS3 from Automationdirect.com.
I have had good success with TD200 series VFDs from Factorymation.com (Drawback, no provisions for braking resistor)
You would have to go with the TD400 series if you want a braking resistor

[Krlerma]

I certainly like my WEG Electric CFW300. It has fantastic programming usb port, if you are into that kinda thing. Super easy to setup. I purchased it thru automation direct.

[BodeRacing]

I certainly like my WEG Electric CFW300. It has fantastic programming usb port, if you are into that kinda thing. Super easy to setup. I purchased it thru automation direct.

I will second the WEG CFW300. I am a little biased but it is a good drive. I know the WEG guys extremely well all the way to almost the very top. The drive is good but the documentation not fantastic. I let the guys that wrote it know that in no uncertain terms. Sat in their office at WEG in Brazil and all they could do was shake their head in agreement on all the documentation deficiencies.

I caved to their relentless sales pressure to try their drives (we buy A LOT of motors from them) and I bought a CFW300 3 hp drive for my South Bend 16" lathe with a 3hp motor. I like it a lot. Very good low end speed and torque control. Much better than I expected for the money. You do need to set it up in sensorless vector mode and tune it.

You also need dynamic braking. That means for the CFW300 drive you need to buy the 3hp. Its under $300. This is the model you want:

drive
https://www.automationdirect.com/adc/sh ... 10p0b2db20 (but its out of stock)

recommended resistor
https://www.automationdirect.com/adc/sh ... br-400w040

Marshall Wolf Automation has them in stock for a couple less dollars but I don't know about resistors. You would have to call them. But Automation Direct could drop ship it - WEG has 185 of them in stock in Duluth, GA.

https://www.wolfautomation.com/catalogs ... 10P0B2DB20

Make sure you follow VFD installation best practices including cable separation and shielded motor leads. See my blurp below from another one of my posts:

There are 3 sources of what I refer to as stray currents caused by VFDs. Stray currents cause bearing failure in motors and equipment, and can cause nearby electronic equipment to misbehave or even fail. Been there done that many times (actually I fix it not create it). Normally stray currents don't hurt bearings in equipment this size, but in testing I catastrophically failed both bearings in a 120 vac fed VFD 1 hp motor in 70 hours.

The stray currents are caused by common mode voltage generated by the drive. Common mode voltage means that the voltage between the neutral and ground is not zero. This causes common mode current flowing in unwanted paths.

First is circulating current. Not usually an issue in motors this size and no action is required.. Solution is an insulated opposite drive end bearing in the motor.

Second is stator to rotor capacitive currents. Usually not much of an issue in equipment of this size. Solution is a ground brush on the drive end of the motor.

Last is the most important. Stator to frame capacitive currents. This is what usually gets you in trouble in equipment of this size. The common mode currents are in the motor frame and WILL get back to the drive (back plane of the drive). You need to control this current path. This is where the shielded cable comes into play. A proper shielded cable will be the preferred low impedance path from the motor frame to the drive. The shield must be well high frequency bonded at the motor and drive. High frequencies don't want to travel in regular wire, even short pieces. The shield needs to be directly bonded to the motor frame and the drive. High frequency strap can be used for the connections if kept short.

Not practical for most folks, but the way to verify proper installation is to put a Rogowski coil around the motor leads and measure the cable summation current. You want to see zero high frequency current flow.

In addition, to protect against cross talk (what you refer to as EMI), even with the shielded cable, keep the motor leads at least 3 inches from all other cables and 6 inches from very sensitive cables.

This is proper VFD installation. I have been trying to get a VFD installation paper done for an IEEE conference for a few years now, but just haven't gotten to finishing it.

[RaptorMachine]

Hey Guys, thanks for all the help and info !!! greatly appreciate it !!! getting super excited to getting this machine running..

this is the vfd i ended up purchasing ..

https://www.factorymation.com/TD400-2003-13PH

with the braking transistor...

Joe

[martyscncgarage]

Hey Guys, thanks for all the help and info !!! greatly appreciate it !!! getting super excited to getting this machine running..

this is the vfd i ended up purchasing ..

https://www.factorymation.com/TD400-2003-13PH

with the braking transistor...

Joe

Should do you well.

[RaptorMachine]

Did some work on the machine today.. replaced all the bijur metering blocks, cleaned out all the lines, replaced a few, cleaned the automatic oiler, replaced the filter, had the electronics cabinet blasted and powder coated.. pretty good match... re-installed it, test fit the backplane, now its back out.. will start drilling and mounting the electronics !