On Mon, 19 Aug 2013 14:15:10 -0700, Gunner Asch
wrote:

On Mon, 19 Aug 2013 14:22:08 -0500, Karl Townsend
wrote:

Packing line upgrade time...

My bin dump water pump is the largest noise maker in the system. I
quickly tried a VFD a couple years ago and it SQUEALED far worse than
the excess motor noise. Just as pleasant as listening to chalk squeal
on a blackboard.

Anyway, this time I want to buy a 1/2 hp VFD that doesn't have carrier
wave noise. Suggestions? BTW, the unit will be located 75' of wire
from the motor. Is a reactor needed in this case?

Karl

Most..not all...but most VFDs do NOT squeal. Of all the ones Ive
installed over the past 16 yrs...only one..a Hitachi 3/4hp on a drill
press squealed.

Automationdirect.com is a very good place for inexpensive drives

http://www.automationdirect.com/adc/...-Hz_Control%29

http://www.automationdirect.com/adc/...-Hz_Control%29

The GS1 drives will probably do you just fine. If you need any bells
and whistles..the Gs2 drives will suit your needs.

Ive installed probably 75 of them to date....all worked as advertised
nicely.

The GS-2 drives typically are used on Lathes to replace bad
vari-drives..usually Hardinge lathes. Its cheaper to install a drive
than it is to repair/replace the vari-drive..by a significant amount,
given Hardinge's rape you/dry pricing.

Gunner

Can you move the drive closer to the motor temporarily, just for
experimentation purposes? It's a whole lot easier to remote the
control wiring from the VFD back to where the operator is sitting.

Is the pump motor Inverter Duty rated? If you have an antique motor
out there, it could sing no matter what you do - they are made to take
60 Hz, Period, and you'll start vibrating laminations with any
inverter harmonics.

And then you make hot spots in the windings, and they start shorting
internally and provide an escape route for the Magic Smoke.

And if the pump motor's a goner, may be cheaper to replace the whole
thing. Variable Speed Pumps for swimming pools are hitting wide use -
meaning they're getting seriously cheaper. And the drives are already
integrated with the motor, and a pump body and debris strainer.

-- Bruce --