Opion Poll. best vfd's

The Mitsubishi A800 series drives are very well built. To use the 200Hp example above,

FR-A840-03610 is rated for 200HP (260A) Normal Duty (150% OL for 60s, 200% OL for 3s, at 50degC). If the application is a variable torque load like a fan or pump it could be used in either Light Duty (250 HP, 325A, 120% 60s, 150% 3s, 50degC) or Super Light Duty (300Hp, 361A, 110% 60s, 120% 3s, 40DegC)

Mitsubishi build their own drives and their own power components unlike most others

There are drives out there with poor hardware reliability and performance records (Schneider/Altivar, TB Woods, and Lenze/ACTech come to mind) but, other than these known bad actors, I believe your best VFD choice is the one that gives you the best competent LOCAL support. And, preferably without additional charge.

That leaves room for a large number of brand names but, even with the best hardware, lack of support is a deal breaker.

I've been applying and commissioning VFD's for almost 30 years now and I'm not ashamed to say that I reach for the Tech Service Phone Line pretty quick when things don't seem to be going right. Nothing poisons a Brand's image faster, in my view, than incompetence in the person on the other end of the Tech service line.

And, I might as well say it here, it seems clearly foolish to commit to a single brand name when you have a broad spectrum of applications in your facility. Some brands are especially good at one type of application and no good at all with others. Some are attractively priced at certain levels of sophistication and too pricey for other levels.

You have to keep your brain engaged. Forget loyalty. Reliability and support give you long term value and that is worth focusing on.

I second Dick's comments wholeheartedly. My gripe with Siemens and GE was not just with drive problems, but at least as much because of lousy support. With both manufacturers, on more than one installation, I had to figure out the problems myself because the technician couldn't.

^ +1

We have a lot of older AB drives that had been very robust. (1336, 160's, 70's) But as they have failed after 15-20 years of service they have been replaced with PF4, PF40 and now PF523. As with everything in our society now (appliances, TV's, stereos, industrial electronics, etc.) everything is being built as less robust throw away. So we find the newer drives less robust and less cost as the old ones.

We also use Yaskawa, Automation Direct G3 and tried a Danfoss.

Programming is easiest (more straight forward) on AB's & G3. Yaskawa and Danfoss have more parameter sets, many of which are related and requires more extensive programming to set-up.

I noticed nobody mentioned Toshiba. Royal pain to setup- cryptic setup symbols etc. But run forever afterwards. I've got old G3's in the field that refuse to die. AS1 seems to be a tough drive also. They standup to power line cap switching spikes when others go up in smoke.

Had very good luck with the AB PF700's also. Drive Executive makes setup easy. 4 and 40 series have the same power unit as the Automation-Direct GS3. Not bad drives as long as they aren't pushed. Good luck so far with the 523 - 525's. Jury's still out on the 750 series. I repair drives and have seen the 753 DC bus caps break out if badly jarred. Caps are supported only by the terminal screws which are offset from the center of the cap. (weird design)

AutoDir GS3's are OK. Have setup several using Modbus control.

Tom Jenkins said:

My favorite would be Eaton Cutler Hammer, but I have had good luck with many different brands.

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I'd have to agree with you there as well. We had Eaton drives in the desert, minimal protection, and never a failure.