Good VFD's

[csmitty]

So thinking I might keep this 2hp monster grinder if I can find a decent and affordable VFD. Seems a much more attractive option than a phase converter. Been reading the Fuji brands are good and the older GE partnership ones. Any other suggestions? Would like have 115V 1ph input but could live with 230V if need be.

 

[fordcragar]

Not sure what you mean "decent and affordable VFD", but I bought a couple of VFD's from http://www.factorymation.com/ a couple of years ago. I'm happy with the drives and they were reasonably priced. At least compared to what I paid for one ten years ago.

 

[DocsMachine]

So thinking I might keep this 2hp monster grinder if I can find a decent and affordable VFD. [snip] Would like have 115V 1ph input but could live with 230V if need be.

-For 2HP, 230V in will be a requirement. I don't think you can get a 110V VFD for anything bigger than a 1HP motor.

Personally, I have two from Automation Direct, one from ACTech, and three from GE. All of them have been pretty much 100% reliable. I got a good deal on the three GE's, slightly used, but if/when it comes time to buy another, chances are It'll be more AD's, since that seems to be the best value-per-cost I can find. (They're not cheap no-names from eBay, but are still fairly inexpensive.)

And for your grinder, you will either need to get the optional braking resistor, or set the VFD to unpowered/coast when shut off. (In other words, no controlled braking or ramp-down.) Otherwise it'll trip out, and coast down anyway. Won't hurt the VFD- at least it shouldn't- but you'd have to reset it before starting the grinder again.

Also, if you just use "coast", you'll have to let the wheels come to a nearly complete stop before restarting, else it'll trip out again.

I found this out when (temporarily) running my 2HP Queen City 12" pedestal grinder on one of the Automation Direct VFDs. It worked, if operated as I said, but now I just run it off my rotary converter.

Doc.

 

[csmitty]

Yea I had pulled up those GS2's and looked like a good option. Looks like at a min probably be around $250. Paid next to nothing for the grinders. Was more in fuel to go pick them up. Probably just keep one though.

 

[DocsMachine]

Yeah, cost is one of the drawbacks to a VFD, though keep in mind, it's a cost often well offset by the usually-cheap asking price of the 3-phase machine. My Queen City cost me $50- an equivalent Baldor would have been $2500 new, or $1200 to $1500 used.

In my case, I wound up with enough machines that buying a rotary, in addition to several VFDs, was worthwhile. I have four machines, for a total of six motors, that would have cost me over $1200 in VFDs. But since none really need the features of a VFD (don't need variable speed on the big grinder, and don't need to reverse the bandsaw, for example) a single $250 rotary takes care of them all. ('Course, I already had a motor for the idler, which saved quite a bit.)

Doc.

 

[BevoZ06]

Since one of my sons is a volunteer firefighter, I thought the title was referring to good volunteer fire departments.

 

[Altec]

Since one of my sons is a volunteer firefighter, I thought the title was referring to good volunteer fire departments.

Same.

Is getting the motor rewound out of the question?

 

[DocsMachine]

Is getting the motor rewound out of the question?

-Yes. Single and triple-phase motors are very similar, but different enough that the conversion would be difficult at best, if not impossible.

It'd be kind of like trying to convert a gas engine over to diesel, or vice-versa. Yeah, there's a lot of similarities (near-identical layout of crank, rods, pistons, even cam and lifters, intake and exhaust valves, etc.) but there's enough difference that converting would require so much work and modification that you'd be better off simply replacing it with the preferred style of engine.

Doc.

 

[Outlawmws]

VFD would be far cheaper...

 

[toolz]

I have also used freq drives from FactoryMation in the past, they worked fine, and have since had good results and pretty good pricing on drives from Automation Direct.

 

[csmitty]

Yeah, cost is one of the drawbacks to a VFD, though keep in mind, it's a cost often well offset by the usually-cheap asking price of the 3-phase machine. My Queen City cost me $50- an equivalent Baldor would have been $2500 new, or $1200 to $1500 used.

In my case, I wound up with enough machines that buying a rotary, in addition to several VFDs, was worthwhile. I have four machines, for a total of six motors, that would have cost me over $1200 in VFDs. But since none really need the features of a VFD (don't need variable speed on the big grinder, and don't need to reverse the bandsaw, for example) a single $250 rotary takes care of them all. ('Course, I already had a motor for the idler, which saved quite a bit.)

Doc.

Yea I agree. I paid I think $67 for that 2HP Baldor and 1.5HP Powermatic. Course the Powermatic was the wrong one they gave me. Oh well. Those are the only two I have now and no real foreseable expansion in 3ph. Other than finding a smoking deal. How is the power quality from the home built setups?