The motor on our SP-20 isn’t getting power anymore, even though nothing is wrong with the electrical system. We think it might be a problem with the capacitor. Does anyone have experience with this? I appreciate any thoughts. Thank you.
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I vote that you take the motor to an electrical repair shop rather that try to fix it yourself. Why risk further harming the motor? I haven’t looked in a while, but as best I remember, replacement motors are not generally available.
your friend may be right, if its swollen its not working anymore. normally they are clued in the housing with doublesided tape, just pray it out carefully. shorten the contacts with a well insulated screw driver first and unload it. here is a link where i got mine: https://www.ebay.com/itm/323445601383
here are the specs. they should be written on your capacitor as well.
BrandVanguardMFD/uF53-64 uFVoltage110-125 VacFrequency50/60 HzTemperature Range-40°C to +65°C-40°F to 149°FCountry of OriginMexicoWeight0.20 lbsDiameter1-7/16” ±.02”Length2-3/4” +.02”/-.03”CaseRound PhenolicConnection TypeFour 1/4” Spade TerminalsResistorNoneUPCN/ACertificationsUL Recognized
Thank you! My friend removed the capacitor from the press, and told me its not working anymore- and I should replace. Its actually swollen and stuck inside its metal housing right now.
Hi Ernst, I have the exact same motor. My label looks the same except a different ID#.
motor label
here is a schematic of the motor
oh, one other important thing: unload the capacitor before you touch it.
good timing, i have a motor from a sp-20 on my work bench just now. maybe its the same type of motor that you have. i will add a pic of the motor label. it is a capacitor start induction motor. here the capacitor is controlled by a centrifugal switch and only used at the start of the motor, than its cut off. additional it has a thermal protector device that also could be the problem. without knowing more how you measured the electrical power AT the motor itself its hard to help more. it could also be that the toggle switch gave up. if you are not really familiar with motors, best is: disconnect the lines, take it out, and bring it to a motor repair shop.
Rob Miller says:
“A capacitor in an AC synchronous motor primarily serves to create a phase shift between the current and voltage in the motor’s auxiliary winding, enabling the motor to generate a rotating magnetic field. This rotating field is crucial for starting the motor and keeping it running efficiently. The capacitor helps improve the power factor and ensures that the motor starts quickly and operates smoothly by balancing the phases of current in the motor’s stator windings, especially in single-phase motors, where it enables the creation of a second phase needed for motor rotation.”