Capacitor marking typically includes the following information to help you understand its specifications:
1. Capacitance Value
- The capacitance value is usually marked directly on the capacitor. It is expressed in farads (F), but in most common capacitors, it is shown in microfarads (μF), nanofarads (nF), or picofarads (pF).
- For example, a capacitor might be marked as "100μF", which means it has a capacitance of 100 microfarads.
2. Voltage Rating
- The voltage rating indicates the maximum voltage that the capacitor can safely withstand without breakdown or damage.
- It is marked on the capacitor body and is usually given in volts (V). For instance, a capacitor may have a voltage rating of "25V", meaning it can handle up to 25 volts of applied voltage.
3. Tolerance
- Tolerance shows the allowable deviation from the stated capacitance value. It is expressed as a percentage.
- Common tolerances are ±5%, ±10%, or ±20%. For example, a capacitor marked "100μF ±10%" can have a capacitance value anywhere between 90μF and 110μF.
4. Temperature Coefficient
- Some capacitors may have a temperature coefficient marking, which indicates how the capacitance changes with temperature.
- It is usually given in parts per million per degree Celsius (ppm/°C). A negative temperature coefficient means the capacitance decreases with an increase in temperature, while a positive coefficient means it increases with temperature.
5. Manufacturer's Code or Part Number
- This is a unique code assigned by the manufacturer to identify the specific capacitor model. It helps in sourcing the same type of capacitor in case of replacement or for referring to the capacitor's technical specifications in the manufacturer's data sheet.
For example, a capacitor might be marked as "470nF 16V ±10%", indicating a capacitance of 470 nanofarads, a voltage rating of 16 volts, and a tolerance of ±10%.