jbcapacitors blog

Keywords: Polarised, DC power supply circuit, large capacitance.

Electrolytic Capacitors are generally used when very large capacitance values are required. Here instead of using a very thin metallic film layer for one of the electrodes, a semi-liquid electrolyte solution in the form of a jelly or paste is used which serves as the second electrode (usually the cathode). The dielectric is a very thin layer of oxide which is grown electro-chemically in production with the thickness of the film being less than ten microns. This insulating layer is so thin that it is possible to make capacitors with a large value of capacitance for a small physical size as the distance between the plates, D is very small.

The majority of electrolytic types of capacitors are Polarised, that is the DC voltage applied to the capacitor terminals must be of the correct polarity, i.e. positive to the positive terminal and negative to the negative terminal as an incorrect polarisation will break down the insulating oxide layer and permanent damage may result. All polarised electrolytic capacitors have their polarity clearly marked with a negative sign to indicate the negative terminal and this polarity must be followed.

Electrolytic Capacitors are generally used in DC power supply circuits due to their large capacitances and small size to help reduce the ripple voltage or for coupling and decoupling applications. One main disadvantage of electrolytic capacitors is their relatively low voltage rating and due to the polarisation of electrolytic capacitors, it follows then that they must not be used on AC supplies. Electrolytic's generally come in two basic forms: Aluminum Electrolytic Capacitors and Tantalum Electrolytic Capacitors.

Structure

A photoflash capacitor is an electrolytic capacitor used in flash cameras, professional flashes, and also in solid-state laser power supplies. Their usual purpose is to briefly power a high-voltage flash tube, used to illuminate a photographic subject or optically pump a laser rod. As flash tubes require very high current for a very short time to operate, photoflash capacitors are designed to supply high discharge current pulses without excessive internal heating.

Photoflash Aluminum Electrolytic Capacitors are very special capacitors and need very high quality and professional  technology. I have friends told me that jb Capacitors Company produce very good quality photoflash electrolytic capacitors. JSU Series--Photo-Flash-Lug-Aluminum-Electrolytic-Capacitors. Here is the datasheet link:http://www.jbcapacitors.com/Aluminum-Electrolytic-Capacitors/JSU-Photo-Flash-Lug-Aluminum-Electrolytic-Capacitor.html

jb capacitors company is very strong on Aluminum electrolytic capacitors, including snap-in, screw type and lug type.

Snap-in Aluminum Electrolytic Capacitors is widely used on power supply. If the end product is industrial motor, some customer may requires to add a mica sheet of plastic layer or other non-flammable material between the Aluminum electrolytic body and PCB. As we know, the motor has vibrations, and it keeps running 24 hours, so that the capacitor will be very hot. The piece of plastic layer is used as insulation to prevent the capacitor from shorting itself.

jb capacitors company not only produce MKT MKP Film capacitors, also produce high quality Screw 
terminals Aluminum Electrolytic capacitors, some people called Large can aluminum electrolytic capacitors, I.E. Snap-in, Screw, Lug type. Long load life, high ripple current...

Recently jb strongly recommend screw type aluminum electrolytic capacitors, with very high quality, widely use in power supply, UPS, Welding Machines, filter etc...

See below our strong series:
JMJ--Screw terminal aluminum electrolytic capacitors, 2000hours at 85C'---cross: Epcos B41456,B41458/ B43456,B43458/ B43564, B43584/ B43455, B43457 CDE: CGS series
JML--Screw terminal aluminum electrolytic capacitors, 2000hours at 105C'--Cross: 
Epcos B43740,B43760/B41560,B41580/ B43450,B43770(high ripple current)
JMN--Screw terminal aluminum electrolytic capacitors, 5000hours at 85C'
JMQ--Screw terminal aluminum electrolytic capacitors, 5000hours at 105C'

jb capacitors company is very strong on Aluminum electrolytic capacitors, including snap-in, screw type and lug type.

Snap-in Aluminum Electrolytic Capacitors is widely used on power supply. If the end product is industrial motor, some customer may requires to add a mica sheet of plastic layer or other non-flammable material between the Aluminum electrolytic body and PCB. As we know, the motor has vibrations, and it keeps running 24 hours, so that the capacitor will be very hot. The piece of plastic layer is used as insulation to prevent the capacitor from shorting itself.

Tape and Reel is a process of packing surface mount devices (SMD's) by loading them into individual pockets comprising what is known as a pocket tape or carrier tape. The carrier tape is wound around a reel for convenient handling and transport. The reel is enclosed in a reel box before it is finally shipped to the customer.

A Tape-and-Reel holds hundreds-to-thousands of surface mount devices. This saves in labor and will further reduce manufacturing costs for automated circuit board assembly.

jb capacitors company manufactures and markets SMD Aluminum Electrolytic capacitors. They are both with tape-and-reel package.

JCS - 2000H at 85°C SMD Aluminum Electrolytic Capacitors

JCK- 1000H at 105°C SMD Aluminum Electrolytic Capacitors

JMQ is one of our screw type aluminium electrolytic capaciotrs. it can be used in electrical source panel.

And one of the panel function is that it can control pulse current discharge in plasma generator device.

Pls. click the link for the specification.

http://www.jbcapacitors.com/pdf/JMQ-5000H-at-105-Screw-Aluminum-Electrolytic-Capacitor.pdf

Aluminum is used for the electrodes by using a thin oxidization membrane. Large values of capacitance can be obtained in comparison with the size of the capacitor, because the dielectric used is very thin. The most important characteristic of electrolytic capacitors is that they have polarity. They have a positive and a negative electrode.[Polarised] This means that it is very important which way round they are connected. If the capacitor is subjected to voltage exceeding its working voltage, or if it is connected with incorrect polarity, it may burst. It is extremely dangerous, because it can quite literally explode. Make absolutely no mistakes.

Generally, in the circuit diagram, the positive side is indicated by a "+" (plus) symbol.

Electrolytic capacitors range in value from about 1µF to thousands of µF. mainly this type of capacitor is used as a ripple filter in a power supply circuit, or as a filter to bypass low frequency signals, etc. Because this type of capacitor is comparatively similar to the nature of a coil in construction, it isn't possible to use for high-frequency circuits. (It is said that the frequency characteristic is bad.)

The aluminum foil that makes up the plates in the electrolytic capacitor is treated in a few different processes to make it work properly and more efficiently. The most important process is the anodizing of the foil. Anodizing is a process that forms a very thin layer of aluminum oxide on one or both sides of the foil when the foil is immersed in an acidic solution and direct current is applied to the foil (one lead of the DC power supply is connected to the foil and the other is connected to a conductive plate in the acidic solution). This layer of aluminum oxide is the dielectric (insulator) and serves to block the flow of direct current. To increase the surface area on the foil (and ultimately increase capacitance), the foil can be etched by a chemical process. This would be done before the anodizing.

Electrolytic caps are more complex than film capacitors and are generally used for larger capacitance values (0.47 microfarad and higher). The electrolytic capacitor generally consists of 2 layers of aluminum foil with a layer of paper material between the plates. It looks a little like this: