Just got a Hurst 3001-001 115vac synchronous. This seems to be the motor of choice for many DIY'ers. As received I wired it with the supplied capacitor and it starts and run fine until ... I put a pulley on it. It won't start with the pulley installed and will only run if I hand start it. After that it seems to be right on the edge torque-wise. My platter weighs about 6 lbs and spins very freely. Using a round rubber belt.
Is it normal to have to hand start this motor under load?
TKS.
Is it normal to have to hand start this motor under load?
TKS.
Shaded pole motors are the motors for turntables as they synchronise to the mains frequency. They do not use a startup or direction capacitor and have a lot of torque. They are also very inexpensive and reliable.
Here is a selection from different suppliers;
shaded pole motor | eBay
Here is a selection from different suppliers;
shaded pole motor | eBay
Shaded pole is just a way to impart direction bias in an AC motor, be it synchronous or asynchronous. A motor needs to be synchronous to drive a turntable at constant speed, the Hurst uses 2 phase and a run-capacitor, a more efficient and powerful technique that shaded pole.
The Hurst motor can't overcome the static friction of the platter system at rest it seems. A more powerful motor is needed if there's not a mechanical fault adding unnecessary friction to the system. Perhaps the round belt is too tight or too stiff, thin flat belts are commonly used with turntables.
The Hurst motor can't overcome the static friction of the platter system at rest it seems. A more powerful motor is needed if there's not a mechanical fault adding unnecessary friction to the system. Perhaps the round belt is too tight or too stiff, thin flat belts are commonly used with turntables.
No drag. The motor does not want to start when the pulley is installed. The pulley is a three step for 33/45/78 and weighs about 2 grams. If I put on a lighter pulley the motor will start. When connected to the turntable with a thread it will run only if I hand start it. Just seems to not have the torque needed for the application although many seem to use it. I am at a loss to understand.
Here's a thought - power down, discharge the cap, disconnect one end of it and test its value - perhaps its wrong or faulty and leading to sub-standard motor performance?
Soon as I get home from holiday travel will do as you suggest. It seem logical that the cap could be the cause here ... Thanks very much for the tip.