Verify that your selected capacitor has at least the number of connection terminals per connection post as the original motor capacitor. Just a fan and compressor right now. replaced with a 440vac 10 mf motor run capacitor. Most start capacitors have two terminals per post, and most run capacitors will have either 3 or 4 terminals per post. The unit is quite old, and had been previously stripped of all it's supporting electronics. When testing a run capacitor many techs pull the leads off and use the capacitance setting on their meter to test the capacitor. A wide variety of run capacitor sizing options are available to you, I'm having difficulty finding information about the proper start and run capacitor for a compressor motor on a glycol chiller.

Nearly all start capacitors … Run capacitors are designed to expand the top to break the circuit to the terminals when they fail, so if the top of a run capacitor is domed rather than flat, it is bad. Case shape. capacitor sizing ... Capacitors are sized to suit the motors starting and running needs, they need to be replaced with ones of the same mfd rating, you can go higher on the voltage rating, but not lower. The start capacitor sizing doesn't worry me to much as the momentary possible over sizing shouldn't be a problem.
Capacitors are sized using an electrical property called inductance in the motor winding circuit containing the capacitor. A typical run capacitor rating ranges from 2 µF to 80 µF and is either rated at 370 Vac or 440 Vac. As a rule of thumb you can go plus or minus 10% on a run capacitor, and 10% of 35 is 3.5. single phase blower motor, original factory cap was 370vac 10mf. You'll find that you cannot apply the 10% rule to any cap lower than 50 mfd. There are no other standard cap sizes within 10% of 35, and thus no substitutions can be made.
The motor also has a substantial resetable thermal overload I'd like to replace the run capacitor with a properly sized one, so I'm looking for … The nearer they run to their maximum voltage rating the quicker they wear out. Alibaba.com offers 1,043 run capacitor sizing products. A properly sized run capacitor will increase the efficiency of the motor operation by providing the proper “phase angle” between voltage and current to create the rotational electrical field needed by the motor.

Hi everybody, Please advise the effect to energy efficiency and other ill effects if a motor start capacitor is oversized similiar to the following scenario.