VFD help/advice

[chaseme5]

Our vfd is a lenze m3220b. 240v 3 phase input. 2hp 3 phase output. It failed again after 2 yrs. of service. The drive is running a HSC20d pump. 1.2 SF, 6.4 Amp motor. The bridge rectifyier failed on the VFD. Service to the property is 240V 1 phase.

My question is can I use a 240v 1 phase VFD instead of a 3 phase 240v VFD for the input? What hp drive do I need to run a 2hp motor on a 1 phase 240v input.

I believe the drive is bing damaged due to an unballanced load on the input since the drive input is 3 phase. Using 3 phase in is lowering the hp to the motor by 50%.

 

[Valveman]

If you want something that will last, you will git rid of the VFD and replace it with a Cycle Stop Valve and use a regular single phase motor. The CSV will also lower the horsepower by 50% when needed. Any pump will do this when the flow is reduced, you don't need three pahse or a VFD to make that happen. VFD's are made to sell, CSV's are made to last.

 

[chaseme5]

There is too much cost involved to change everything. Does anyone know the parameters needed on a vfd to run a goulds hsc20d pump?

 

[Valveman]

What would be the most expensive, replacing the VFD every two years or so, or changing it over to a regular system that will last 20 to 30 years without any more expense? Don't be like most people who call me and wait until you have replaced the VFD 3 or 4 times before figuring out it just isin't dependable.

Why do I know this? Because I studied and used VFD's 25 years ago. That right, 25 years ago. There is nothing new about a VFD. They have been making new designs trying to solve the problems of VFD's for 30 years. The problem is, the laws of physics will never let them fix resonance frequency vibration, bearing currents, harmonics, voltage spikes, and many other things. The newer designs of VFD's have a few bandaids for these problems, but they cannot fix the problems unless they can change mother nature. Not only are the VFD's problematic themselves, but they are also very hard on the motor, and greatly shorten its life as well. VFD's were made to sell, not to last. That way you just keep pumping money to the manufacturer and installers.

But yes I can tell you that when converting single phase to three phase, you need to double the size of the VFD. So you will need one sized for a 5 HP to be able to not overheat running a 2 HP while converting single phase to three phase. I could even pick a model from several different manufacturers, but I really don't want to suggest something that is already giving you problems. You know what they say about doing the same thing over and over and expecting different results?

 

[chaseme5]

The more information link about your products does not work on your website.

 

[Valveman]

Try this link.
http://www.cyclestopvalves.com/simple/home.php

You will need to start by getting a single phase motor. Then you have the options of using either a huge pressure tank, or a CSV and a small pressure tank. Either way is preferable and will last many times longer than any VFD.