Recommended VFDs for my Bridgeport?

I recently purchased a nice used Bridgeport mill. Always wanted one so I'm pretty psyched. It has a 1.5 hp 3 phase 220VAC motor. I only have residential single phase in my garage. This mill also has a variable speed head, so technically I don't need variable speed capabilities. But from what I've heard, VFDs are much more efficient than static 3 phase converters, which apparently lose a lot of power in the conversion. I see on ebay there are a zillion choices for VFDs, almost all Chinese stuff. I don't want to get burned buying cheap Chinese junk. Although maybe some Chinese stuff is ok, don't really know. So I'm hoping someone can steer me in the right direction to a popular/commonly used/well respected unit. And also clarify if I should get a VFD or maybe a static converter. Not sure what I heard was accurate, so some clarity there would be appreciated as well. Thanks....

Actually, mills seem to do OK on static converters, but the price difference may not be all that big.

I think Hitachi has a number of units that will work without derating including that power level, and so does TECO, and Invertek. There are others. Some will go direct from 120V, others want 230V input.

You can match the VFD to the motor for any that do not need a derate. So if they have a 1.5 HP unit (Invertek does, IIRC) you can use that. Otherwise 2 HP will also work fine.

Generally, while HP is a good way to look at the matching of motor to VFD, a better way is current. Look at the full load current (FLA) of the motor, and verify that the continuous rating of the VFD is at least a bit over that, preferably 15% to 30%.

The VFD will start the motor slowly, so no large current inrush. Easier on the motor, easier on the breakers, no slamming of gears in the machine.

[...The VFD will start the motor slowly, so no large current inrush. Easier on the motor, easier on the breakers, no slamming of gears in the machine...]

If you program it to do so. FWIW Most of my machines are set for about a 10 second start. Braking OTOH can be much quicker (via programing) if needed.

3¢

Edit I use Altivar, Hitachi, GE, Woods, and Automation Direct. They all work with no problems.

Thanks for the responses. Ok, so it sounds like I definitely want a VFD instead of a static converter. The slow start, braking functions and much lower power loss sound really good. Is there a sweet spot where you get all of those features with a decent price and also good quality? If so I'd love to hear the recommendations. I'll check out the brands you mentioned as well WHH. Thanks to all...

Both Factorymation and Driveswarehouse get good reviews over at owwm.org. Jack Forsberg over at canadianwoodworking also sells drives that he has made to his specs and sells pretty cheap. Dave

Look on ebay for Allen bradley 1300 series.

Good units and old tech so priced good.

Got out 3 hp one for 199 delivered.

For any vfd download the manual before purchase and perform a "virtual install" meaning read instructions and be certian you understand them and that the unit will operate your machine in your place.

Check to see if it will work with single phase input and what size is needed in single phase for your motor and last confirm voltage as units like Allen bradley or other commercial grade (preferred) come in many different voltage varients.

Avoid consumer grade or one off made in China stuff as support is questionable at best.

For the vfd it is not smart to save a few bucks by selecting unknowns.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk

One of the issues you will run into running a VFD on a varispeed head is that you are running the belt/discs in the exact same spot and will get wear much faster on your motor shaft. Normally we get people who run the VFD's on step pulley heads or just a static phase converter on the vari speed heads.

Just wanna put that out thare, since we see this alot when we do head rebuilds.

Jon
H&W Machine Repair

Thanks everyone for the replies. Having trouble finding an Allen Bradley that's the right size and doesn't require 440 3 phase input. Still searching, but did find this one on Amazon.

Amazon.com: LAPOND VFD Drive VFD Inverter Professional Variable Frequency Drive 1.5KW 2HP 22V 7A for Spindle Motor Speed Control(VFD-1.5KW): Home Improvement

I know it's a cheapie Chinese, but it has a lot of positive reviews and is priced right. Might take a chance on it. And even though it has an "Engrish" manual, apparently the Chinese company does provide good user support (unusually).

And Jon/HW -I would not use the VFD to vary the speed of the cutter bit. I would pretty much use it just to get 3 phase power at my home and run the motor at full speed all the time as it would be without a VFD. I would vary cutter speed using the step pulley only (and back gear) and try to ensure I avoid the wear problem you mention. I also like the soft start feature to help keep impact on the motor and gears minimized. Thanks for the heads up either way though.

That's yet another offshoot of the cheap Chinese garbage drives they have been dumping on the market the past few years. Most of them all come out of the same factory but they keep changing the name on the outside (or have no name at all) to avoid the long term fallout of their junk. In fact "Lapond" is not the mfr of the drive, it is the name of the Amazon reseller, who also sells iPhone cases, water hoses and Christmas decorations. Be wary of all the good reviews, a lot of them are reviews by shills.

I am new to this site but have question i have a 10 hp lathe 220/440 PH3 60hz only have single phase power is a VDF a good choice or do I need a phase converter?

Well I went ahead and ordered the 2 hp/1.5kW "Lapond" VFD. It's a $100, the manufacturer claims a 1 year warranty, it has 35 almost five star reviews from verified purchasers (who are unlikely to be shills). I know it's Chinese from a dealer with little/no reputation and so it may blow up on me. But I was really having a hard time finding a reputable one that was even capable of receiving single phase 220VAC input, much less one that was affordable. So I figured I'd give it a shot. If it survives a year without trouble, odds are it'll survive a lot longer. And if it fails within a year, Amazon is pretty good about getting your money back. I'm willing to take a little risk, we'll see what happens. I'll let everyone know how it works out.

Thanks for the advice in the meantime.

I would be extremely surprised if any ONE of those reviews is actually from anything other than a 'shill'... they have extremely clever ways of making those reviews happen, but yes, if you look through the reports of those who've tried the side-door VFDs, the results are essentially universal.

My Bridgeports have Allen Bradley 1305s running on 240v single phase. I bought mine as used pull-offs, in a pallet. Out of eight drives, I had only eight good ones, and despite the age, and sitting in storage, I never bothered to go through a capacitor-reforming process.

Note that although many drives are not 'advertised' to accept single-phase input, many do. About half of the A-B 1305 drives are LISTED as capable... in my experience ALL of them would do it just fine. A-B's 1336 product line does too. Units that 'do not' are frequently so because there's 'phase loss detection' fault process in their firmware that shuts the drive down if the input voltage or current becomes aysmmetrical. In many cases, this protection can be disabled by software, and sometimes 'fooled' by connecting a non-polarized capacitor between one of the hot leads and the unused lead.

Aside from the other advantages noted above, most VFDs have the ability to 'overspeed' the motor. I have my drives set to run substantially higher than 60hz, and in doing so, it means I can make a cut using a lower drive ratio, and have effectively more torque at the tooth.

What you'll find, is that varying speed with the VFD is a MUCH more desireable operation, than using the variable head arrangement.

As others have recommended, I would recommend a VFD as well. With a VFD, you won't need to de-rate the machine as you will with a Phase Converter. I used an EATON MMX12AA7D0F0-0 VFD on my 1.5HP Bridgeport. This VFD is rated 240V Input and 2HP Output. Hope this helps if the one you ordered doesn't work out.

-30cal

VFD for Bridgeport

I just noticed this thread and thought I would add my 2c....

I have a Mazak 18x80 manual lathe with a 7.5 hp 3 ph motor. Marshall Wolf automation suggested a Fuji drive running off 220v single phase. This is a 3 ph drive running off single phase, so you have to de-rate it to ensure you don't overload the drive. They recommended a 15 hp drive, that cost me just $590 + tax, free shipping. The installation and setup was quite straight forward. I also bought a large braking resistor which enabled me to program the drive to stop the lathe very fast - just like an emergency stop ! I use the normal start / stop controls on the lathe, so the VFD is "invisible". I run it off a 40 amp 230 volt circuit, but 30 amp would have been fine.

Secondly I bought a mechanical ironworker with a very large flywheel. The motor is a 2.2 kw 3 phase (about 3 hp). Again M-W and Fuji helped me select a drive. In this case the problem was the inertia of the 350 lb flywheel. I Initially used the inverter off my lathe to check out how much power I needed. I don't remember all the numbers, but the press needed the 3 hp motor to start the flywheel, then only took 4 amps (220v) to run the machine, or about 1.25 hp. With this info, and help from M-W I installed a 5 hp Fuji drive for $230 !! I set the start-up ramp to about 5 seconds so as not to overload the drive and it works great.

Thirdly just getting a Seiki 3 hp knee mill (think Bridgeport). This machine has a variable speed head (cones & belt). I'll be installing another 5 hp Fuji drive, for $230. I have a 220v 20 amp loop around my shop, so I'll just plug the drive in - so simple.

The guys at M-W and Fuji tech support are very helpful and will take the time to support us low-tech mechanical guys - can't recommend them enough. The set-up and programming is very straight forward. I can't imagine messing with a cheap Chinese import when these high quality drives are really quite inexpensive.

This technology is so cheap and simple it opens up a whole lot of industrial 3 phase equipment for the small shop environment.

Good luck
Bob

I bought the fancier Lapond for my lathe due to the ability to add an external braking resistor and also it is sensorless vector (apparently). I did this based on the reviews and also I contacted the seller and got the manual in PDF ahead of time to ensure it would be legible and intelligible. The manual was just as good as any other, it was easy to program, and has been working great. I provided a review. I hightly doubt all of those reviews are fake. I think you'll do just fine for the price.