Any advise in purchasing/ setting up a VFD?

[HMH]

Hey folks,

My "arn" collection grew a bit over the weekend to include a nice 1964 Powermatic PM65 cabinet saw....complete w/ (2)-3' cast iron extension wings.

The seller described the motor as being a "newer 2HP, 3PH", so my original plan was to find a 2-3HP 1PH motor and swap it out. Upon inspection however, the "newer" motor turned out to be a brand-spankin' new 2HP Baldor. I think I'll hang onto it.

So, that turns my attention to supplying power to the saw through the use of a converter. I don't see myself picking up "too many" more 3PH machines, so at first glean, I'm leaning towards a VFD setup vs. a static phase converter.

In addition to the more standard, lower 3PH voltages, the motor is capable of operating on 440V-3PH, so I think I would prefer to find a "surplus industrial" VFD, as opposed to the more popular, asian made, TECO units, (I certainly don't intend to knock the quality or reputation of the asian made units, I'm sure they make a fine product - it's just somewhat outside of what I am accomplish with my tool "collection".)

All of that said, outside of the very basics, I am green when it comes to the details of VFD setup. If any of you have any advise/ experience/ contacts for surplus industrial equipment, etc. with this technology, I would love to hear it.

Thanks!

 

[Jim Kunzweiler]

I would stay clear of the surplus vfds. The new ones such as the Hitachi (sold at Drives Warehouse.com and other online suppliers) are inexpensive and much more reliable.
http://www.driveswarehouse.com/Drives/AC+Drives/Phase+Converter+VFD/X200-022NFU1.html

I've also found that if you like to collect old iron that 3 Ph tools sell for less than 1 Ph. You can pick up some good bargains. As long as you work alone and only use one tool at a time you can power several tools off the same VFD.

 

[Alan in Little Washington]

I wouldn't be too concerned about the source of the VFD most are pretty reliable these days, and even some of the US brands are made offshore. If something goes bad it usually only affects the VFD and not the motor. I have three VFD's- one on my lathe (Mitsubishi), one on my drill press (Motortronics), and one for tinkering (Baldor), currently waiting for an application. Many of the VFDs come loaded with programmable features. You will likely want to wire it for remote start/stop and possibly set it for ramp-up soft start, but that's about all, so you don't need a fancy unit.

If you do decide to get a VFD from Ebay or other surplus source, make sure you carefully check out the specs- you can't use one that doesn't run on 220V single phase (some require 440V, 3 phase input), and you might want to be sure you can get or find the manual. Also, carefully check the specs. Some VFD's must be de-rated when powered by single phase. Finally you will need to understand and set the operating parameters via software programming. Without a manual it can be very difficult to do so.

 

[eyekode]

If your motor is capable of running at 220v I would go with that. The last time I looked I didn't see any reasonably priced VFD's that take 220v single phase and output 440v 3 phase.

Also I will recommend the Teco units. Yes they are inexpensive but they work fine. If your switch is not magnetic you can continue to use it on the low voltage inputs like I did.
The one reason I can think o to go with a more expensive unit is to get better environmental sealing. But this really depends on where you are going to mount it.

Good luck!
Salem

 

[mkepke]

I think Heath is saying he wants the 'look' of a heavyweight industrial VFD to complement his industrial machines.

That sounds dangerously like 'accessorizing' ;-)

No advice to offer on the VFDs - I use Tecos and whatever else is cheap and reliable.

-Mark

 

[bholcombe]

Is the VFD setup really going to be cheaper and more reliable than the rotary phase converter? All the VFD's I've ever used for work did not appreciate being fed just one phase power, and I haven't seen any that had a built in voltage transformer to increase voltage. They all seemed capable of providing lower output voltages than the feed, but they never claimed to go up in voltage for the output. If the VFD you need exists, it doesn't sound cheap.

 

[HMH]

Thanks for the feedback so far folks.

After reading up a bit, I'm torn between the VFD or Rotary converter route - Static is out. I only run one tool at a time, (not incl DC), so I'm thinking that the VFD will win out.

Mark - no danger of "HD - accessorizing" here! I was primarily concerned about the quality of the inexpensive VFD units, (Teco, etc), but from everything I've read, no one seems to have a problem.

Bholcombe - I haven't READ, (my only experience at this point), that a VFD is any more/ less reliable that a rotary converter, only that it is better suited (ie less expensive) for single machine, relatively small HP demand. I'd love to hear your take on the subject though. There would be no need to increase the voltage across the converter, the plan is to run 220V through both phases. My original comment mentioning 440V was only when I was considering adding a transformer and using surplus industrial equipment vs. a new VFD - that option has been pulled off the table at this point based on the discoveries I mentioned above.

Thanks again folks - by all means, keep it coming!

 

[aplpickr]

Most modern VFDs have some 250 programmable parameters. You will need about fifteen of them. Make sure that motor overload trip is enabled. Buy local so that there is somebody available that is willing to help with the parameters. An extra $50 will be worth it when the questions are needing answers while reading the ~300 page manual. The average house electrican does not understand this either! Do not settle for an online manual, insist on a HARD copy. Most programming has a built-in timer (30 seconds) for the next key punch before it takes you out of programming. Toggle the setting back and forth while making your decision. Review and record the entire program after the last change. Most motors need to trip at 15% overload. Before setting this parameter make sure that the VFD figures this in and you are NOT supposed to figure this amount. FLA (full load amps) is probably what they want, the VFD usually fiqures the 15%. Decel time needs to be at least 5 to 10 seconds or the overload will trip. I do not recommend one VFD for several motors, their overload settings will be different.

 

[mgberry]

I just went through this recently with some of my older equipment. I wanted to make sure I left myself enough head room for larger HP machines. I ended up going with a 7.5HP RPD for a number of reasons. I think if you are never going to run over 2-3HP then a VFD might be fine. I just felt that why invest in something that I was going to be limited by what arn I can purchase.

I went with Elmia and they make a great product using new Reliance Motors. I have no affiliation with them, but was impressed by their knowledge and desire to help during installation.

Matt

 

[mkepke]

Heath - my mis-read of the situation.

I'll second (or third) the recommendation for the Teco. I have two of them myself and they are obviously very popular with others too. They are pretty easy to program - as long as you take your time reading the manual.

-Mark

 

[Sully]

Another vote for a Teco. I have several and a RPC as well. The RPC is used mainly for debugging 3PH motors and running larger HP motors.

The Tecos I have work fine and I haven't had any issues with them. Make sure you match the motor specs (FLA primarily) to the VFD. Don't buy based on HP alone.