Soft start and maybe soft stop for DC Well Pump

[Johnatl]

I have been digging and tinkering to come up with a soft start and soft stop for a 24 VDC at 5 amps well pump . The reason is that I want it to start up with as little torque as possible . This is what wears and tears on the suspension, wiring, and piping . So far I have using a power MOSFET gated by a RC time circuit with additional bypass IDEC "Ice Cubes" . Ideas and suggestions ? This is a first post .

 

[Reloadron]

My best guess would be to soft start ramping up to full speed using PWM (Pulse Width Modulation). Then ramp down for stop. I would likely choose a small easy to program micro chip. This is far from my forte but something like a small uC driving a Logic Level Gate MOSFET. Ramp up and ramp down. Generally I do not suggest using a uC but this application seems to beg for using one. Again, I am far from a PIC programming guru but we do have several members here who are quite good with them.

Ron

 

[ronv]

Maybe an in rush current limiter like this?

https://www.electro-tech-online.com/custompdfs/2011/11/powerthermistor.pdf

 

[Johnatl]

I am trying to go way back to the future with controls easily understood by Ag work force . They need to also be way high survivabilty for EMP both the conspiracy foretold and the God made too well Georgia Lightning . I had not thought about the thermister and it would be a good thing to encorporate in the solution .

 

[KeepItSimpleStupid]

www.Jameco.com has a PWM motor control kit for about $20. It has inherent soft start logic even if you operate it at a set speed. I used it to drive a solenoid near an extremely thin like a millimeter or so, $1000 piece of glass (filter) and i was really happy.