Dingfeng Capacitor---How does a start capacitor start motor?(Part 1)

Dingfeng Capacitor---How does a start capacitor start motor?(Part 1)

Dingfeng Capacitor---How does a start capacitor start motor?

How Does Start Capacitor Help Start Motor - Permanent Split Capacitor Motors or PSC Motors use run capacitors to help the motor be more efficient while running. The start capacitor gives the motor a boost on start up. The run capacitor helps the motor run more efficiently. Many types of HVAC equipment use PSC motors as blowers and pumps.

So in HVAC you will have motors in most applications, including residential and commercial, that use capacitors for the motor no matter the application or purpose. These motors are a step above the shaded pole type of motor which was the original type of motor used for many applications.  A shaded pole motor could have power applied to it and not move or turn backwards from its intended direction. With the advent of PSC motors those problems went away. PSC motors will always start in the direction for which it is engineered to start with a few exceptions. Even in those few exceptions the PSC motor will fight to turn in the intended direction.

How Does Start Capacitor Help Start Motor - The Basics

While the PSC motor uses a run capacitor to increase its efficiency while running there are also some HVAC motors used that also require a start capacitor to help it start. A start capacitor is used in applications where the motor needs a boost on start-up to overcome pressure or some kind of force. Remember an AC induction motor goes from zero RPM’s to full speed (RPM’s) in a split second so if the motor has to start up against some kind of force like the high pressure that a refrigeration circuit would have for a compressor to start against then some help will be needed to give the compressor motor a little boost on start-up.

We introduce the start capacitor which will only be in the circuit for a split second. Then a relay will take it out of the circuit. The relay is the potential relay or less commonly a current relay. A potential relay works off of back EMF while a current relay works off of current. So after covering the basics how does a capacitor work to help the motor? The answer is that a capacitor whether it is a start capacitor or a run capacitor changes the phase angle when the motor is powered up. By changing the angle you give the motor a little more push. If you push straight down on the rotor you expending energy in the wrong way to get the most out of the rotor. However, if you push from an angle then you change the ease of which you apply the energy. 

As the top three capacitor manufacturers in Wengling, we have engaged in producing capacitor for over 28 years and we are trying to be better.We believe one day Dingfeng Capacitor will exist in every corner of the world by means of its reliable quality and good reputation. By the way, Dingfeng sincerely welcome all the friend to visit our company and hopes to have a good communication and double-win partnership with all of you cause Dingfeng capacitor is always on the way to be better! Your views are the driving forces of Dingfeng! I hereby on behalf of all the members of Dingfeng, thank all of you for the long-term supporting and concerning of our growth.

ac motor running capacitor: http://www.dfcapacitor.com/products2062600/Ac-motor-running-capacitor.htm

fan capacitor: http://www.dfcapacitor.com/products2062602/Fan-capacitor.htm

air conditioner capacitor:http://www.dfcapacitor.com/products2062601/Air-condition-capacitor.htm

Lighting capacitor:http://www.dfcapacitor.com/products2062606/

Lighting-capacitor.htmStarting capacitor:http://www.dfcapacitor.com/products2062603/Motor-starting-capacitor.htm

power capacitor: http://www.dfcapacitor.com/products2062604/power-capacitor.htm

If you have any question about our company or dingfeng capacitor, pls contact us:


Foreign trade : Katrina

Mobile: +86 15067446433

Tel: +86-574-88034090

Fax: +86-574-87111961

E-mail: sale05@dfcapacitor.com

QQ: 1298975481

Skype: 15067446433