I know from reading the posts about motors, that there are many experts here,
& I have got a situation that I need some help with.
Rewired a average sized horse barn, simple job. Owner asks if I would look at a motor control that operates a 6 position horse exerciser, turned by a "Leeson" 1HP DC motor. He tells Me that "One day it just took off, & gradually sped up until it was too fast for the horses to walk."
I looked at the controller, seemed simple enough, 120 volt supply Stop/Start Run/Brake Forward/Reverse switches, & a
speed control.
I called the Mfg. "Leeson", they suggested replacing the controller, checking & or repairing the old one wouldn't be worth it,since a new unit was around 200.00
Owner said to go ahead & order it.
When it arrived, I replaced it, went through the setup instructions exactly.
It acted the same, ran too fast, & was unable to slow it with the speed control.
I called the "Leeson" Rep, talked to some Tech support Guys, & they said "Sometimes a DC motor can act that way if it's going bad"
This I didn't understand, but then again, I don't have much experience with motors & their controls, so I bit.
(This is the moment I wish I hadn't got involved with this)
I explained all of this to the Farm Owner, said He would replace the motor Himself, so I only charged Him for the Control & shipping, & was on My way.
Well, He called Me the other day, paid 450.00 for a new 'Leeson" DC motor,replacecd it & nothing changed. Still runs too fast, & unable to slow it with the controller.
I am stumped, there's nothing left to change. This setup worked perfectly for years, Owner took it apart & moved it from Texas to Kentucky, & it worked correctly for about a year....until that day it started "running too fast."
Now, does Anyone have a clue what may be wrong here ? The control is 120 or 240, but has always worked on a 120 volt supply.
I want to try & help this Customer correct this, but after a new control & motor, I don't know where to start, ...but I do know where to look for the answer, I told the farm Owner about this Group, & said if it could be done, these People would know how.

Thanks, Chuck