Is there a reasonably priced soft start control for a typical single phase motor?

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chino valley
Thanks to Reach and Cary,, I've been looking at VFD's and regular pumps for my 2 wells I just drilled.

for my particular application,, i don't think a VFD is really necessary but the soft start seems like a huge benefit. I've installed a couple of soft start electronic units on some 1.5 hp AC units. i am wondering why i can't find any soft start controls for a regular 1.5 hp pump,, just seems to make sense it will last longer.

does anyone know of a soft start system for a typical 1.5 hp franklin motor?
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Cary Austin
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Lubbock, Texas
Soft starters for HVAC maybe a good idea, but not for submersible pumps. A submersible motor has to be at least up to 50% speed before there is any lubrication for the thrust bearing. The longer it takes to get to speed, the more damage is done to the bearing. A reduced voltage soft start will not effect the speed, only the amount of torque. You can make a reduced voltage starter by simply using the longest length of the smaller wire possible for a 1.5 HP pump. Using 190' of #14 wire will cause a 5% voltage drop at load. This will cause there to be 20% less starting current and 36% less torque on start up, and is all the soft start you need.

Also, soft start is not important if you are not starting the pump over and over. Using a Cycle Stop Valve limits the number of starts so much that how you start is no longer important. Soft start is only important if the pump is starting 100-300 times per day. But then eliminating the cycling on off would be the solution, not a soft starter.

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