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CAPACITORS
A capacitor is a component that stores electrical energy
between two metal plates separated by an insulator or
dielectric. The unit of capacitance is called a farad. A 1 farad
capacitor is typically pretty big, depending on the voltage it can
handle. So you typically see capacitors rated in microfarads (millionths
of a farad).
A capacitor is similar to a battery in that they both store
energy however a capacitor can release its entire charge in a fraction
of a second while a battery would take minutes to completely discharge
itself.
The information needed when working with capacitors is the
voltage, capacity, tolerance and temperature. Different dielectrics will allow you to vary the size and each
dielectric has unique properties that affect the temperature and
tolerance. The dielectric will usually determine the cost of a
capacitor. For example, tantalum, which is a very common dielectric, is
a precious metal and will usually cost more than a capacitor made of
ceramic.
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| Capacitor manufacturers have created codes to help mark the product so it
can be identified and the use them in their part numbers so that you can be
assured that the part number you order will have the correct characteristics for
your application. Here are some of the more common
codes. |
| Letter symbol |
Tolerance of capacitor
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| B |
±0.10% |
| C |
±0.25% |
| D |
±0.5% |
| E |
±0.5% |
| F |
±0.1% |
| G |
±0.2% |
| H |
±0.3% |
| J |
±0.5% |
| K |
±0.10% |
| M |
±0.20% |
| N |
±0.05% |
| P |
+100%, -0% |
| Z |
+80%, -20% |
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First symbol
(a letter)
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Low temperature requirement
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Second symbol
(a number)
|
High Temperature requirement
|
Third Symbol
(a letter)
|
MAX. Capacitance change over temperature
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| Z |
+10 deg. C |
2 |
+45 șC |
A |
+1.0% |
| Y |
-30 deg. C |
4 |
+65 șC |
B |
±1.5% |
| X |
-55 deg. C |
5 |
+85 șC |
C |
±2.2% |
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6 |
+105 șC |
D |
±3.3% |
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7 |
+125 șC |
E |
±4.7% |
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F |
±7.5% |
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P |
±10.0% |
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R |
±15.0% |
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S |
±22.0% |
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T |
+22%, -33% |
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U |
+22%, -56% |
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V |
+22%, -82% |
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| Code |
Voltage |
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Code |
Voltage |
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Code |
Voltage |
|
Code |
Voltage |
|
Code |
Voltage |
| 0D |
2V |
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1A |
10V |
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2A |
100V |
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3A |
1KV |
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4A |
10KV |
| 0E |
2.5V |
1B |
12.5V |
2B |
125V |
3D |
2KV |
4B |
12.5KV |
| 0G |
4V |
1C |
16V |
2C |
160V |
3F |
3.15KV |
4C |
16KV |
| 0J |
6.3V |
1D |
20V |
2D |
200V |
3G |
4KV |
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| 0K |
8V |
1E |
25V |
2E |
250V |
3H |
5KV |
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1H |
50V |
2F |
315V |
3J |
6.3KV |
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2G |
400V |
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2W |
450V |
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2H |
500V |
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| Most capacitors are fixed at a specific capacitance
however there are variable or trimmer capacitors that allow you to
adjust the capacity. Another important aspect of a capacitor is whether
it is polarized or non-polarized. A polarized capacitor has a positive
and a negative lead. Polarized capacitors cannot tolerate reverse
voltages. If a polarized capacitor is installed backwards in an
application it can result in an explosion. The negative (cathode) side
of a polarized capacitor should always connect to the ground. |
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| Some of the manufacturers you can find at TEDDS
are: |
| Aerovox |
Electronic Film Concepts |
Jamicon |
Novacap |
| American Technical Ceramics (ATC) |
Electrocube |
Jennings |
Panasonic |
| Johanson |
Electronic Concepts |
Kanthal Globar |
Richey |
| Arco |
Elgen |
Kemet |
Roderstein |
| American Suzuki Capacitors (ASC) |
Elna |
KOA |
Rubycon |
| AVX |
Elpac |
Luxon |
Saha |
| BC Components |
Evox |
Maidia Development Corp (MDC) |
Sprague |
| Bishop |
General Electric (GE) |
Mallory |
Syfer |
| Cal-Chip |
High Energy |
Matsuo |
TDK |
| Component Research |
Illinois Capacitor |
Murata |
Tusonix |
| Cornell Dubilier
(CDE) |
IMB |
NEC |
United Chemicon |
| Daewoo |
International Components Corp (ICC) |
Nemco |
Venkel |
| Dearborn |
Iskra |
Nichicon |
Vishay |
| Dielectric Labs |
ITW Paktron |
Nissei |
Wima |
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TEDDS has almost every style of capacitor in stock and priced right
for you.
Here are just some of the styles we have for you:
- AC Motor run/ Motor start
- Aluminum Electrolytic (Axial, Radial, Surface Mount, Snap-in)
- Ceramic (Axial, Disc, Radial, Surface Mount, Trimmer)
- Dip Guard
- Dipped Mica
- Film (Axial, Radial, Surface Mount)
- Glass (fixed and variable)
- Plate Capacitors
- Tantalum (Axial, Radial, Surface Mount)
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Some of the many types of dielectrics TEDDS can offer are:
| Air |
Mica |
Polyester |
Porcelain |
| Ceramic |
Paper |
Polypropylene |
Tantalum |
| Electrolytic |
Polycarbonate |
Polystyrene |
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