Understanding start loads

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I have a large mill that has a 20 horse motor on it. It doesnt have a clutch so everything is is ,start,stop, start, while positioning everything, that is the way it was built. I havent used it much, but im wondering what kind of power consumption am i going to be dealing with when i start using it. I know when running it isnt running anywhere near the 54 amps but when i have to bump it multiple times it will pop a 50 amp breaker. My power company already loves me but im just trying to figure out if its just huewie or does it use a lot of power just getting positioned. I dont want to bump into a different teirDo not argue with an idiot. He will drag you down to his level and beat you with experience.
Reply:You could invest in "soft start" switch gear which will reduce starting amps and then you can adjust the time it ramps up to full torque which by that time it will be doing the work. You'd want to check to see how it will take repeated short start-stop cycles like you use for positioning.Ol' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:What size mill do you have?I found machine tool manufacturers will go nuts on horse power to sell machines.Dave

Originally Posted by idacal

I have a large mill that has a 20 horse motor on it. It doesnt have a clutch so everything is is ,start,stop, start, while positioning everything, that is the way it was built. I havent used it much, but im wondering what kind of power consumption am i going to be dealing with when i start using it. I know when running it isnt running anywhere near the 54 amps but when i have to bump it multiple times it will pop a 50 amp breaker. My power company already loves me but im just trying to figure out if its just huewie or does it use a lot of power just getting positioned. I dont want to bump into a different teir
Reply:You could just upgrade to a 60 amp breaker.ChrisAuction Addict
Reply:No its legit 20 horse, 5’x10’ table, that  is feet, about 35000 lbs its a decent sized horizonal boring mill.  im more worried about being bumped on power charges. Is inrush amps really a thing or just old wives tales? Im used to large machines always having a clutch so you jsut leave the motor running but not on this machine.Do not argue with an idiot. He will drag you down to his level and beat you with experience.
Reply:It would be very hard to use 3 hp I would lower the horse power to 5 to 7½hpDave

Originally Posted by idacal

No its legit 20 horse, 5’x10’ table, that  is feet, about 35000 lbs its a decent sized horizonal boring mill.  im more worried about being bumped on power charges. Is inrush amps really a thing or just old wives tales? Im used to large machines always having a clutch so you jsut leave the motor running but not on this machine.