Motor and VFD recommendation

I recently purchased a Pinacho L1/180 lathe, it currently has a 3.6hp 600V 3 phase motor. I want to switch out the motor for a 220V 3 phase and run it from a VFD. I am wondering what Motor and VFD combo you guys would recommend? My budget is very flexible say under $2000. The lathe is older but has had very little use and has been well cared for.

I would look for a 5HP motor with rated speed of about 1150 RPM at 60 Hz and a 5 HP rated VFD. The lower than 1750 RPM motor allows you to maintain more motor power at low frequencies, You can still make the motor run at 1750 RPM by using the VFD to increase the frequency to 90 Hz. But a 5 HP at 1750 RPM motor will still have plenty of power if you don't crank the frequency too low.

I said 5 HP because it is a very common motor rating in the US/Canada and 3.6 HP is probably something more common in Spain. I have, in the past found some very cheap prices on brand new three phase motors on eBay, as low as $1 when no one else bid.

Larry

I would buy a 3-5hp motor of the same rpm. If you can buy one with the same shaft diameter and at least as long a shaft. I recommend a TEFC motor to keep out oil and chips. I hope it is a commom mount size.
On a big motor buried in a cabinet like that I like to cut the existing cord right near the motor. Then I put a new short cord on the new motor and wire on a new male/female plug set to the cords. This eliminates a lot of wiring headaches when installing the new motor. The plug set can be any thing, you find cheap, that works. it does not need to match up to anything else anywhere. If the lathe came with a oddball plug use that type since you already have half the pair
Bill D

Buy a WEG 5 HP motor and WEG CFW drive. Buy the motor at the same RPM as the motor you already have.

Bill D said:

I would buy a 3-5hp motor of the same rpm. If you can buy one with the same shaft diameter and at least as long a shaft. I recommend a TEFC motor to keep out oil and chips. I hope it is a commom mount size.
On a big motor buried in a cabinet like that I like to cut the existing cord right near the motor. Then I put a new short cord on the new motor and wire on a new male/female plug set to the cords. This eliminates a lot of wiring headaches when installing the new motor. The plug set can be any thing, you find cheap, that works. it does not need to match up to anything else anywhere. If the lathe came with a oddball plug use that type since you already have half the pair
Bill D

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That's a handy idea, thanks Bill.

I vote TENV . . . and like others have stated - match shaft diameter and length if possible.

TENV will give you a few advantages:

1. Higher Inertia will deliver smoother finish on parts
2. TENV motors are designed to run at full torque @ zero speed - you need not concern yourself with overheating the motor when running the motor at near zero speed
3. As mentioned for TEFC, no entry point to the motor for debris - and - TENV has the additional advantage of no fan noise

I also recommend Nidec / Control-Techniques drives - they are hands down the best performers we have worked with whether fed with single phase or 3-phase. And - they have native English manuals that are superior to anything we have seen from other drive manufacturers.

If you have room - here is a great combo, especially if the encoder works
OR . . . as previously mentioned - you could go with a 6-pole motor

Lots of options for good motors. On the drive side - if you want encoder feedback for additional torque control / smoothness at less than 50 RPM, then get a drive with provisions for encoder feedback - this would could be an M400 or higher (i.e. M600..70x) . . . if no encoder is used you can go with a lower feature M200 or M300

I am new to this community and I have to say, you guys are amazing! Thanks for all the info. Still putting it all together. I live in a fairly remote location so getting this all together is gonna take time.

The OP hasn't said, and doesn't need to use the VFD as the speed control. He could run the motor at 60Hz, or close to, and use the lathe's existing spindle speed arrangements. This makes motor sizing a lot simpler.

A TEFC or TENV motor may be physically bigger then other types. This means they may not fit in a tight space even if they are the same frame size. Some motors have huge wiring boxes that can get in the way or have to be moved to let them fit in the allotted space.
Bill D

I would go with a 5hp tefc 1140 rpm...Phil

Mark Rand said:

The OP hasn't said, and doesn't need to use the VFD as the speed control. He could run the motor at 60Hz, or close to, and use the lathe's existing spindle speed arrangements. This makes motor sizing a lot simpler.

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+1 Allow lesser HP, smaller overall.

General rule of thimb, AC or DC, is that if you NEED variable speed to be avalable at full power, more "base" HP needs to be put into place because..

AC drops-off as RPM is dialed below base RPM.

DC suffers at RPM above base RPM.

That's "over-generalized", perhaps. But look around. It is common to provide more power whenever the "variable thing" needs to be done well.

As far as sourcing? Well "Canada" in general is not short of modern high tech and plenty of choices.

The issue is Newfoundland/Labrador/The Maritimes having long and slender transport networks and low local population density. That makes stocking distributors or recyclers of used-but-good awfully scarce!

I would take a different approach for this size lathe, and it all comes down to availability of motors in your location and shipping costs to your location. Some/most of the US eBay vendors do not have shipping to Canada, those that do are expensive and you have customs/import duty. You would need to contact them as to costs. I agree that a TEFC or better yet TENV motor would be the best option. If you can get a inverter/vector motor (i.e. one that must be run off of a VFD) you will get a wider operating range and pretty much full torque down to 0 RPM. I would go with a 3 Hp motor for several reasons, the stock motor was 3.6, you will not notice any difference, shipping will be less expensive, 3 Hp VFD's with single phase input are readily available at reasonable cost. Move up to 5 Hp and you have doubled or tripled you VFD/install costs. You lathe has multiple speeds if you really need to gear it down, but I have a similar sized lathe with a 3 Hp and the motor doesn't flinch and I take it down to 20 Hz. If you can go with a smaller motor pulley size you can optimize these types of motors toward their higher RPM's and get the benefit of the mechanical ratio advantage and a wider speed range. A 6 pole motor is going to be a bigger frame size and offer little if any noticeable performance advantage in this setting. Once again if you can find a 6 pole or 4 pole 5 Hp cheap then it would be a decent option, but factor in the additional costs when going to a higher Hp motor.

The motor below would be my recommendation, if you can get it shipped to canada, otherwise you might go with local motor houses. Most motors will do just fine as a replacement with the voltage spec. you are looking at, chances are the stock motor was a TEFC. This motor can only be run off of a VFD.
3HP Marathon Motor, 182TC, TVB182THTS8028EPL Blue MAX Y527, 230/460V 1.9A 540... | eBay

As far as VFD's well it going to come down to cost and basic features, as you do not need anything high tech for this application. You will require an external braking resistor to aid in stopping and you need to understand that you cannot use a VFD as a power source for the lathe, it must be directly connected to the motor. You bypass the contactors and such, and you should not directly wire the VFD control inputs to your controls. You need some basic control system for safety reasons, you have a foot brake if used you need to send a free run command to the VFD when using it. If this is not a 24/7 industrial setting I think you can get by just fine with mid priced VFD's such as the Teco E510, Hiatchi WJ200, there are a few Fuji models, and sure if you can get a Nidec / Control-Techniques drives at similar cost go for it. I just prefer to keep things simple at this level. Teco E510 is probably the easiest to setup and understand. Cannot recommend any of their lessor model or the Chinese generic VFD's.

This vendor might ship to Canada, or there may be a source in Canada, more to give you pricing.
Purchase 3 HP VFD, 230 Volts, NEMA 1/IP20, Teco, E510-203-H-U at Dealers Industrial
Hitachi, WJ200-022SF, 3 HP, Variable Frequency Drive 230 Volt, 1 Phase Input, IP20, at Dealers Industrial

I made the purchase today. There is so much to choose from that I just went ahead and bit the bullet so to speak. I purchased this motor Premium T-Frame Aluminum Motors - Techtop Canada Electric Motors along with an Eaton DC1 Power XL VFD. Now to put it all together and get it running. Thanks for all the help!