HELP Induction motor knowledge?

reclaimed · 07-19-2006, 07:39 PM

single phase 3 hp induction motor on a shaper won't run. The starter switch engages and the motor gives a little jerk and does nothing else??

redline · 07-19-2006, 09:38 PM

Quote:

Originally Posted by reclaimed

single phase 3 hp induction motor on a shaper won't run. The starter switch engages and the motor gives a little jerk and does nothing else??

Are you sure that this is a single phase and not a three phase motor?
Is it a single phase 110, single phase 220, single phase 440...?
Have you removed the cover on the switch and checked for a loose connection? (with the power off)
If you assist the motor when it first starts will it come up to speed?
Have you disconnected the motor from the gear/pulley that it drives to see if another part of the shaper is bound up?

reclaimed · 07-19-2006, 10:11 PM

220 single phase on a 30 amp breaker and yes to all your questions. Tryed to rope assist with no luck, still just a nudge at the moter when the swich engages. Thank you for your response!

MAS2006 · 07-19-2006, 11:56 PM

Find the motor name plate and post information on it. I worked on induction motor using dynamic DC braking. If cycled to much motor assembly would get hot and not spin load up correctly. Worked if allowed to cool off.

redline · 07-20-2006, 08:25 AM

Is this the first time that you have tried running this machine on this circuit or has this machine been running on the circuit and it has now just started to act up?

Some motors have a starter winding or capacitor that starts it up until it is able to rotate on it own.

How many wires are there inside the motors electrical compartment? 3,6,9? (Not including the the 3 wires from your power source)

There should be a wiring schematic inside the motors electrical compartment.

reclaimed · 07-20-2006, 02:11 PM

the machine has been and was running for a while on that circuit. I ran for about 1/2 hour and shut down, when I returned to the machine it did not respond. After switching on and off several time's the machine did re-start one time for a moment (last death breath)No. of wires 8 -3 from plug 3- from frwd/rev switch and 2-jumpers.

reclaimed · 07-21-2006, 10:05 PM

All the obvious items were checked first, then I bypass the switch to find the motor works fine! After opening the thermal in the magnetic switch marked do not open I discovererd a loose conection in what looked to be a fusable link. The machine is back together and works again,thank you for your response.

redline · 07-23-2006, 10:45 PM

I was going to have you check to see if you had the proper voltage/ampes to the motor but you found the problem

07-19-2006, 07:39 PM	#1
reclaimed Newbie Join Date: Jul 2006 Posts: 6	HELP Induction motor knowledge? single phase 3 hp induction motor on a shaper won't run. The starter switch engages and the motor gives a little jerk and does nothing else??

07-19-2006, 10:11 PM	#3
reclaimed Newbie Join Date: Jul 2006 Posts: 6	HELP Induction motor knowledge? 220 single phase on a 30 amp breaker and yes to all your questions. Tryed to rope assist with no luck, still just a nudge at the moter when the swich engages. Thank you for your response!

07-19-2006, 11:56 PM	#4
MAS2006 Sciencerules Join Date: Apr 2006 Location: Missouri Posts: 61	HELP Induction motor knowledge? Find the motor name plate and post information on it. I worked on induction motor using dynamic DC braking. If cycled to much motor assembly would get hot and not spin load up correctly. Worked if allowed to cool off.

07-20-2006, 08:25 AM	#5
redline Member Join Date: Mar 2006 Posts: 2,083	HELP Induction motor knowledge? Is this the first time that you have tried running this machine on this circuit or has this machine been running on the circuit and it has now just started to act up? Some motors have a starter winding or capacitor that starts it up until it is able to rotate on it own. How many wires are there inside the motors electrical compartment? 3,6,9? (Not including the the 3 wires from your power source) There should be a wiring schematic inside the motors electrical compartment.

07-20-2006, 02:11 PM	#6
reclaimed Newbie Join Date: Jul 2006 Posts: 6	HELP Induction motor knowledge? the machine has been and was running for a while on that circuit. I ran for about 1/2 hour and shut down, when I returned to the machine it did not respond. After switching on and off several time's the machine did re-start one time for a moment (last death breath)No. of wires 8 -3 from plug 3- from frwd/rev switch and 2-jumpers.

HELP Induction motor knowledge?