Examples: Circuit symbol:
s开头的英文名男when the spot is in sight, the positive is to the right'. Examples: Circuit symbol:
Colour Code
Colour Number
Black 0
Brown 1
Red 2
Orange 3
Yellow 4
Green 5
Blue 6
Violet 7
Grey 8
White
9Ignore any letters - they just indicate tolerance and voltage rating.
For example: 102 means 1000pF = 1nF (not 102pF!)
For example: 472J means 4700pF = 4.7nF (J means 5% tolerance).
Capacitor Colour Code A colour code was ud on polyester capacitors for many years. It is now obsolete, but of cour there are many still around. The colours should be
read like the resistor code, the top three colour bands giving the value in pF.Ignore the 4th band (tolerance) and 5th band (voltage rating).For example:
brown, black, orange means 10000pF = 10nF = 0.01µF.Note that there are no gaps between the colour bands, so 2identical bands actually appear as a wide band.For example: wide red, yellow means 220nF = 0.22µF.Polystyrene Capacitors
This type is rarely ud now. Their value (in pF) is normally printed
without units. Polystyrene capacitors can be damaged by heat when
soldering (it melts the polystyrene!) so you should u a heat sink
(such as a crocodile clip). Clip the heat sink to the lead between the capacitor and the joint.
Real capacitor values (the E3 and E6 ries)
You may have noticed that capacitors are not available with every possible value, for example西瓜栽培技术
niceboat22µF and 47µF are readily available, but 25µF and 50µF are not!
Why is this? Imagine that you decided to make capacitors every 10µF giving 10, 20, 30, 40, 50
and so on. That ems fine, but what happens when you reach 1000? It would be pointless to
野有美人
描写四季的诗make 1000, 1010, 1020, 1030 and so on becau for the values 10 is a very small difference,
庆祝国庆的诗歌
too small to be noticeable in most circuits and capacitors cannot be made with that accuracy.
T o produce a nsible range of capacitor values you need to increa the size of the 'step' as
the value increas. The standard capacitor values are bad on this idea and they form a
ries which follows the same pattern for every multiple of ten.
The E3 ries (3 values for each multiple of ten)电鳗放电原理
10, 22, 47, ... then it continues 100, 220, 470, 1000, 2200, 4700, 10000 etc.
Notice how the step size increas as the value increas (values roughly double each time).
The E6 ries (6 values for each multiple of ten)
猪心的营养价值10, 15, 22, 33, 47, 68, ... then it continues 100, 150, 220, 330, 470, 680, 1000 etc.
Notice how this is the E3 ries with an extra value in the gaps.
