These are value capacitors and they are not polarized. Non polarized capacitors they can be connected either way round. They are not damaged by heat when soldering, except for one unusual type (polystyrene). They have high voltage ratings of at least 50V, usually 250V and so on. It can be difficult to find their values and they have several different labeling systems.
How to read non polarized capacitors value
Many non polarized capacitors have their values printed on them but without a multiplier, so knowledge to work out what the multiplier should be is needed.
For example 0.1 means 0.1µF=100nF. Sometimes the multiplier is used in place of decimal point, for example 4n7 means 4.7nF.
Capacitor Number Code is often used on small capacitors where printing is difficult. I have also provide a table of capacitors with their number codes and capacitance in pico Farad (pF), nano Farad (nF), and micro Farad (µF) all HERE
The stages to read them is on below
- The 1st number is the 1st digit
- The 2nd number is the 2nd digit
- The 3rd number is the number of the zeros to give the capacitance in pico Farad (pF).
For example, to read the value of the capacitor below
The 1st number is 1 which is the 1st digit, 2nd number is 0 which is the 2nd digit, and the 3rd number is 4 which means 4zeros (0000)
Therefore we write; 100000pF = 100nF = 0.1µF
Some of the non-polarized capacitors have letters and voltage rating printed on them. Letters on these types of capacitors indicate tolerance and sometimes company’s series.