Choosing a VFD (picking a tree from the forest)

mjs408

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After a long talk with tech support at Wolf Automation. He recommend 2 different options for a VFD that will output to a plug to run both my mill and lathe (until I can afford a second vfd) The Tech recommend a

Fuji FRN0012C2S-7U or Lenze ACTech ESV222N02YXB. He said one nice thing about the lenze is it comes with a downloadable powerpoint on wiring and programming. Also the owners manual is written by native english speakers.

I also see alot of people with Teco Westinghouse A510 and L510 models? They are all similarly priced in the grand scheme of things.

How did you guys figure it out?
 
Selection is based mostly on what's on the motor tag and what input voltage you plan to use. (I assume your input is single phase otherwise you probably wouldn't be asking the question.) If your input voltage is 220V you have more options, with 110V input you are limited to about 1 hp. The motor voltage is also important. Some older motors (typically from schools) will be rated for only 200 volts, in that case you can forget about any VFD that doesn't allow you to set the output voltage (The Teco FM50 is one that doesn't). The next thing is the current required by the motor. It may say amps or FLA (full load amps). The VFD must be able to supply at least that but more is fine. Personally I would only look at VFD's that are "sensorless vector" (again no Teco FM50). I do like and have Teco N3 and the Teco 7300CV drives. I have heard good things about the Hitachi and Lenze drives. I personally also have a cheap Ebay Huanyang but I do NOT recommend that. My first VFD was an FM50 which is fine for the wood shaper it is on but I would not recommend that if you plan using it for changing the speed.
 
The wiring and configuration would be different for a mill and a lathe, so it is a safety issue to use one VFD for both. Also, many VFDs are programmed and tuned (autotune) for a specific motor's characteristics. There are cases where a single VFD operates more than one motor, it must be operated in a V/Hz configuration vs. sensorless vector mode. You also loose the aspects of the motor protection, so each motor it technically supposed to be fused for its individual rating. If you just need 3 phase, you could put together a RPC for less.

Two VFDs would run you around $500 if sized for each machine, which is not much more than the Lenze. I have heard a few issues with the newer Teco L510 and the FM50 is a pretty dated design, so I would be more inclined to recommend the Teco A510, N3 or 7200. The Lenze is a very good VFD, also Hitachi WJ200-022SF and the Automation Direct Durapulse GS3-23PO. You want a constant torque sensorless vector drive, the size is specific to the motor Hp/kW (motor characteristics), and the input/output voltage required.

As far as using a plug, any of these VFDs can be wired to a plug, but it would need to be a 30A 230VAC. There is nothing special about any of these in that regard. The panel breaker should be similarly rated. Maybe if you provide us with the mill and lathe motor specifications/type and how you want them to operate then we can give you some more specifics. In general I recommend a simple 3 wire control with momentary buttons for the mill (or use a remote VFD panel), the lathe is a bit more complicated. Depending on how you want to use the VFD will change the recommended models.
 
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I have a Teco N3 from Wolf Automation on my 2Hp Bridgeport mill. I was disappointed by Wolfs support, they didn't seem to know much about the vfd (they had to go to the mfg to answer my questions). The N3 comes with an optional NEMA bracket so you don't need to mount it in another enclosure to wire it up, which was nice. I also recently purchased a Hopewind vfd for my 3Hp lathe from amazon. I like it too; it's very high quality for a Chinese made vfd and they have excellent US support; it has nice software that makes setup easy through the built in RS485 interface; and it came with a USB to RS485 dongle so it was pretty much plug and play. Programming it through the keypad is easy too. Just be aware that with any vfd there is a bit of a learning curve for programming it and setting it up so good support is important. Of course there is also a wealth of knowledge here on HM.
 
The ratings on those two motors are very close. Close enough so you should be able to set the VFD for the higher current 8.5 amps without any problems (it's only 0.1 amp difference). RPM 1710 vs 1720 is also not really an issue. Shop around, prices vary and so does shipping. I haven't used the Hitachi or the Teco L510. If I buy another one any time soon it would be the N3.

Here are a few that I would think appropriate:

TECO 7300CV Model CV-2003-H1 JNTHBCBA0003AC-U

*TECO N3 Model N3-203-CS-U

Hitachi WJ200-022SF

TECO L510-203-H1-U
 
Here are a few that I would think appropriate: TECO 7300CV Model CV-2003-H1 JNTHBCBA0003AC-U *TECO N3 Model N3-203-CS-U Hitachi WJ200-022SF TECO L510-203-H1-U [/QUOTE said:
Because this is all new to me, and if they are a vfd and a sensorless vector drive and programmable they are all the same to me, what does the extra money of the

Teco N3 get me over a Teco L510 get me? For a 110 more dollars?
 
Because this is all new to me, and if they are a vfd and a sensorless vector drive and programmable they are all the same to me, what does the extra money of the Teco N3 get me over a Teco L510 get me? For a 110 more dollars?

The N3 comes with a cover that makes mounting it without an external enclosure easier. You would need to figure out some way to cover the electrical connections with the L510. This would not be an issue if you mount it inside an enclosure which is probably a good idea**.

The N3 has other features that you probably do not need. I haven't used the L510 but from looking at the manual it appears to have everything I would look for.


**None of my 4 VFD's is in an enclosure, but they do have covers over the connections. Enclosures are probably a better idea.
 
If you have a lot of rotational mass, such as a lathe with a large chuck or running a mill in low gear you can exceed the internal braking capacity of the VFD and would need an external braking resistor. The L510 does not support this option. But if you are looking at just basic functions, then it may be cheaper to consider two L510's as opposed to one more expensive VFD. I still believe that from a safety point of view, the input control wiring (and the input programming) is usually very different between a lathe and a mill. All of the listed VFDs I believe are NEMA 1, so you would want some additional protection to prevent ingress of and metal swarf.
 
If you have a lot of rotational mass, such as a lathe with a large chuck or running a mill in low gear you can exceed the internal braking capacity of the VFD and would need an external braking resistor.

I have a Teco FM50 VFD on my mill (does not support a braking resistor) and it will shut down if I reduce the speed too fast. This is when reducing the speed using the VS that the mill has, not the VFD. There is enough rotating mass in the mill to cause an issue with the VFD. This happens in both high and low gears when reducing speed. A braking resistor would solve this but isn't an option with this VFD
 
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