jb tell you How to test a capacitor

key words: film capacitor. electrolytic capacitor

If you always purchase many kinds of film capacitors, or electrolytic capacitors, you should know how to test the capacitors.
1. Remove the suspected faulty capacitor from the unit. If it's a high powered capacitor, it will still hold a high charge. Discharge the capacitor by using a metal screwdriver with a handle that's insulated. Touch the metal end of the screwdriver to both metal terminals at the same time to discharge any power left in them.
2. Turn on the capacitor tester and make sure it's getting power. Plug in the tester probes according to the instructions on the meter. Set the selector to an OHM scale before testing the capacitor. Some meters will have an OHM setting pre-set for you.
3. Touch the leads together so that the meter will zero out by adjusting the wheel on the meter
4. Note where the meter points to before touching the wires to the capacitor. Then touch the terminals of the capacitor with the red probe, which will go on the left, and the black probe which will go on the right.
5. Watch the pointer on the meter. The needle should move away from the left side, or the infinity, and veer toward the right before returning to the infinity. It should move further to the right when the probes are reversed. This means the capacitor is good. If the needle goes all the way to the right side and doesn't return to the left, or infinity side, the capacitor is bad, or it has shorted out.

jb capacitors is professional manufacturer, offer professional technical service. welcome to contact us by email: info@jbcapacitors.com

jb Film Capacitors

Keywords : radial lead type, axial lead type, plastic film, paper, polystyrene.

Film Capacitors which use polystyrene, polycarbonate or Teflon as their dielectrics are sometimes called "Plastic capacitors". The construction of plastic film capacitors is similar to that for paper film capacitors but use a plastic film instead of paper. The main advantage of plastic film capacitors compared to impregnated-paper types is that they operate well under conditions of high temperature, have smaller tolerances, a very long service life and high reliability. Examples of film capacitors are the rectangular metallised film and cylindrical film & foil types as shown below.

Radial Lead Type
Axial Lead Type

The film and foil types of capacitors are made from long thin strips of thin metal foil with the dielectric material sandwiched together which are wound into a tight roll and then sealed in paper or metal tubes.  These film types require a much thicker dielectric film to reduce the risk of tears or punctures in the film, and is therefore more suited to lower capacitance values and larger case sizes.

Metallized foil capacitors have the conductive film metallized sprayed directly onto each side of the dielectric which gives the capacitor self-healing properties and can therefore use much thinner dielectric films. This allows for higher capacitance values and smaller case sizes for a given capacitance. Film and foil capacitors are generally used for higher power and more precise applications.

jb Film Capacitors list--jb Capacitors Company

jb Capacitors manufactures and markets Plastic Film Capacitors, Including Mylar Polyester Film Capacitor, Metallized Polyester Film Capacitor, Box Type Met Polyester Film Capacitor, X2 Metallized Polypropylene Film Capacitor and Metallized Polypropylene Film AC Capacitor Class-X1 etc.

jb Mini Box Type, 5mm Pitch Size, Stacked MKT Polyester Film Capacitors

Below is some information for current our most popular items, are you still interested in?
If you need faster lead time 7-9 weeks, welcome to check our JFE series, MKT dipped type, also with P:5mm.

JFJ--Mini Box Type, 5mm pitch size, stacked. MKT polyester film capacitors
Cross Arcotronics (Kemet) R82, Epcos B32529, Vishay MKT370,MKT365-367
datasheet: http://www.jbcapacitors.com/pdf/JFJ-Mini-Box-Stacked-Metallized-Polyester-Film-Capacitor.pdf
Bulk & Ammo Pack

jb Capacitors Company Certifications

Key words: ISO logo, SGS logo, VDE logo, cUL logo, UL logo, TUV logo

jb Capacitors Company produce Box type Film Capacitors as below:

  • *JFD--Box Metallized Polyester Film Capacitors
  • *JFJ--Mini box stacked Met Polyester Film Capacitors
  • *JFM--Box Metallized Polypropylene Film Capacitors
  • *JFQ--Double Sided Box Metallized Polypropylene Film Capacitors
  • *JFV--X2 Metallized Polypropylene Film Capacitors, Box type

jb tell you How a capacitor work?

Key words: non-conducting substance, electrons,ultra capacitor, plastic film capacitor Super capacitor, Mylar capacitor, Ceramic Capacitor, In a way, a capacitor is a little like a battery. Although they work in completely different ways, capacitors and batteries both store electrical energy. If you've seen a battery before, then you know that a battery has two terminals. Inside the battery, chemical reactions produce electrons on one terminal and absorb electrons on the other terminal. A capacitor is much simpler than a battery, as it can't produce new electrons -- it only stores them.

Inside the capacitor, the terminals connect to two metal plates separated by a non-conducting substance, or dielectric. You can easily make a capacitor from two pieces of aluminium foil and a piece of paper. It won't be a particularly good capacitor in terms of its storage capacity, but it will work.

In theory, the dielectric can be any non-conductive substance. However, for practical applications, specific materials are used that best suit the capacitor's function. Mica, ceramic, cellulose, porcelain, Mylar, Teflon and even air are some of the non-conductive materials used. The dielectric dictates what kind of capacitor it is and for what it is best suited. Depending on the size and type of dielectric, some capacitors are better for high frequency uses, while some are better for high voltage applications. Capacitors can be manufactured to serve any purpose, from the smallest plastic capacitor in your calculator, to an ultra capacitor that can power a commuter bus. Here are some of the various types of capacitors and how they are used.

  • Air - Often used in radio tuning circuits
  • Mylar - Most commonly used for timer circuits like clocks, alarms and counters
  • Glass - Good for high voltage applications
  • Ceramic - Used for high frequency purposes like antennas, X-ray and MRI machines
  • Super capacitor - Powers electric and hybrid cars

We produce a wide range of film capacitors, including polyester & polypropylene. pls. check our website www.jbcapacitors.com

jb Capacitors Company offer Polystyrene film capacitors

key words: Polystyrene film capacitors, Radial Film Capacitors, Axial film capacitors; As you know, Polystyrene capacitors are not widely available these days.there are only a few suppliers of Polystyrene film capacitors in current market, jb capacitors company can offer you this series.

Polystyrene film capacitors provide extremely low losses, low dielectric absorption, good long-term stability, very high insulation resistance and a small negative temperature coefficient. With their excellent electrical characteristics, Polystyrene film capacitors are ideal for use: tuner & equalization circuits; commercial, industrial & measuring instruments; critical analog circuits; filters, tuned, integrators & sample-and-hold circuits; IF transformers; pulse networks; analogue & digital computing circuits and critical timing circuits such as VCO (voltage-controlled oscillators) and VCF (voltage-controlled filters).

Our JFR-Polystyrene Film Capacitor, including axial and radial type, is with high precision of capacitance.

For more details, pls check our specification link. http://www.jbcapacitors.com/pdf/JFR-Radial-Axial-Polystyrene-Film-Capacitor.pdf

jb Standard SMD Aluminum Electrolytic Capacitor

Keywords: SMD Aluminum, Electrolytic capacitor, Chip Electrolytic Capacitors, Surface Mount Electrolytic Capacitors Nichicon, Panasonic, Rubycon, Panasoic ,capacitor, MKT MKP etc..

jb capacitors company strongly recommend SMD standard type Aluminum electrolytic capacitors.

Our factory not only professional at MKT MKP Film capacitors, but also professional at manufacturing SMD aluminum electrolytic capacitors. We focus on standard type, can offfer many equivalents of big brands, such as Nichicon, Rubycon, Panasonic, Epcos, Arcotronics(Kemet), Sanyo etc...

We produce standard JCS & JCK, I.E. 2000hours at 85C' & 1000hours at 105C', see below our photo and size, welcome you send us inquiry.

case size(DxL):4x5.4~5.8mm, 5x5.4~5.8mm, 6.3x5.4~5.8mm, 6.3x7.7mm, 8x10.5mm, 10x10.5mm

jb Box type Metallized Film Capacitors

Keywords: Box MKT Film Capacitors; Box MKP Film Capacitors; Double sided Box Metallized Polypropylene Film Capacitors.

jb Capacitors Company produce Box type Film Capacitors as below:

*JFD--Box Metallized Polyester Film Capacitors
*JFJ--Mini box stacked Met Polyester Film Capacitors
*JFM--Box Metallized Polypropylene Film Capacitors
*JFQ--Double Sided Box Metallized Polypropylene Film Capacitors
*JFV--X2 Metallized Polypropylene Film Capacitors, Box type.

jb one part of test motor run capacitors

Keywords: motor run capacitors; motor starting capacitors

You can test a motor run capacitor using a 100 watt light bulb and a digital ac volt meter.
Never use an ohm meter to test a motor run capacitor. It is a very inconclusive test and only shows that there is "something" in the circuit. You are essentially "shooting blind".
To test motor start capacitors you will need a 200-300 watt bulb depending on the size.
Caution: capacitors can hold a charge when removed from the circuit unless they have a bleeder resistor. Discharge the capacitor through the light bulb before handling. A capacitor in a working motor circuit cannot hold a charge, it is discharged the instant the power is removed.

Pls. see our JFS--Motor starting capacitors, here is datasheet: http://www.jbcapacitors.com/pdf/JFS-Motor-Starting-Capacitor.pdf. you will find the quality is quite good when you use the correct test mothod.